Not sure if they are relevant but went thru the entire log. Found these references. Guessing related but not sure they tell me personally anything:
2020/09/30 09:56:48 [debug] 17117#17117: *7 http run request: "/remoteDesktopGateway/?"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream check client, write event:1, "/remoteDesktopGateway/"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream request: "/remoteDesktopGateway/?"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream process header
2020/09/30 09:56:48 [debug] 17117#17117: *7 malloc: 56DF0A20:4096
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_read: 812
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_read: -1
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_get_error: 2
2020/09/30 09:56:48 [debug] 17117#17117: *7 http proxy status 401 "401 Unauthorized"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http proxy header: "Content-Type: text/html; charset=us-ascii"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http proxy header: "Server: Microsoft-HTTPAPI/2.0"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http proxy header: "WWW-Authenticate: Negotiate TlRMTVNTUAACAAAACAAIADgAAAAVgonizPkeQUJL8P0AAAAAAAAAAJIAkgBAAAAACgA5OAAAAA9JAEMARQBPAAIACABJAEMARQBPAAEAFABIAE8ATQBFAFMARQBSAFYARQBSAAQAFABJAEMARQBPAC4AbABvAGMAYQBsAAMAKgBIAE8ATQBFAFMARQBSAFYARQBSAC4AaQBjAGUAbwAuAGwAbwBjAGEAbAAFABQASQBDAEUATwAuAGwAbwBjAGEAbAAHAAgAp/sS7DmX1gEAAAAA"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http proxy header: "Date: Wed, 30 Sep 2020 14:56:47 GMT"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http proxy header: "Content-Length: 341"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http proxy header done
2020/09/30 09:56:48 [debug] 17117#17117: *7 HTTP/1.1 401 Unauthorized
Server: nginx/1.14.1
Date: Wed, 30 Sep 2020 14:56:48 GMT
Content-Type: text/html; charset=us-ascii
Content-Length: 341
Connection: keep-alive
WWW-Authenticate: Negotiate TlRMTVNTUAACAAAACAAIADgAAAAVgonizPkeQUJL8P0AAAAAAAAAAJIAkgBAAAAACgA5OAAAAA9JAEMARQBPAAIACABJAEMARQBPAAEAFABIAE8ATQBFAFMARQBSAFYARQBSAAQAFABJAEMARQBPAC4AbABvAGMAYQBsAAMAKgBIAE8ATQBFAFMARQBSAFYARQBSAC4AaQBjAGUAbwAuAGwAbwBjAGEAbAAFABQASQBDAEUATwAuAGwAbwBjAGEAbAAHAAgAp/sS7DmX1gEAAAAA
-------------------
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_read: -1
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_get_error: 5
2020/09/30 09:56:48 [debug] 17117#17117: *7 peer shutdown SSL cleanly
2020/09/30 09:56:48 [error] 17117#17117: *7 upstream prematurely closed connection while reading response header from upstream, client: 192.168.0.187, server: remote.*, request: "RDG_OUT_DATA /remoteDesktopGateway/ HTTP/1.1", upstream: "https://192.168.0.1:443/remoteDesktopGateway/", host: "remote.HIDDEN.net"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http next upstream, 2
2020/09/30 09:56:48 [debug] 17117#17117: *7 free keepalive peer
2020/09/30 09:56:48 [debug] 17117#17117: *7 free rr peer 1 4
2020/09/30 09:56:48 [debug] 17117#17117: *7 close http upstream connection: 16
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_shutdown: 1
---------------------
2020/09/30 09:56:48 [debug] 17117#17117: *7 stream socket 13
2020/09/30 09:56:48 [debug] 17117#17117: *7 epoll add connection: fd:13 ev:80002005
2020/09/30 09:56:48 [debug] 17117#17117: *7 connect to 192.168.0.1:443, fd:13 #9
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream connect: -2
2020/09/30 09:56:48 [debug] 17117#17117: *7 posix_memalign: 56DE47D0:128 @16
2020/09/30 09:56:48 [debug] 17117#17117: *7 event timer add: 13: 60000:535061225
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream request: "/remoteDesktopGateway/?"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream send request handler
2020/09/30 09:56:48 [debug] 17117#17117: *7 set session: 56D911A0
2020/09/30 09:56:48 [debug] 17117#17117: *7 tcp_nodelay
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_do_handshake: -1
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_get_error: 2
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL handshake handler: 0
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_do_handshake: 1
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL: TLSv1.2, cipher: "AES256-SHA256 TLSv1.2 Kx=RSA Au=RSA Enc=AES(256) Mac=SHA256"
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL reused session
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream ssl handshake: "/remoteDesktopGateway/?"
2020/09/30 09:56:48 [debug] 17117#17117: *7 save session: 56D911A0
2020/09/30 09:56:48 [debug] 17117#17117: *7 old session: 56D911A0
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream send request
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream send request body
2020/09/30 09:56:48 [debug] 17117#17117: *7 chain writer buf fl:1 s:1251
2020/09/30 09:56:48 [debug] 17117#17117: *7 chain writer in: 56DD8130
2020/09/30 09:56:48 [debug] 17117#17117: *7 posix_memalign: 56DE1D50:128 @16
2020/09/30 09:56:48 [debug] 17117#17117: *7 malloc: 56DDCC88:16384
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL buf copy: 1251
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL to write: 1251
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_write: 1251
2020/09/30 09:56:48 [debug] 17117#17117: *7 chain writer out: 00000000
2020/09/30 09:56:48 [debug] 17117#17117: *7 event timer del: 13: 535061225
2020/09/30 09:56:48 [debug] 17117#17117: *7 event timer add: 13: 60000:535061235
2020/09/30 09:56:48 [debug] 17117#17117: *7 http upstream process header
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_read: -1
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_get_error: 5
2020/09/30 09:56:48 [debug] 17117#17117: *7 peer shutdown SSL cleanly
2020/09/30 09:56:48 [error] 17117#17117: *7 upstream prematurely closed connection while reading response header from upstream, client: 192.168.0.187, server: remote.*, request: "RDG_OUT_DATA /remoteDesktopGateway/ HTTP/1.1", upstream: "https://192.168.0.1:443/remoteDesktopGateway/", host: "remote.HIDDEN.net"
2020/09/30 09:56:48 [debug] 17117#17117: *7 http next upstream, 2
2020/09/30 09:56:48 [debug] 17117#17117: *7 free keepalive peer
2020/09/30 09:56:48 [debug] 17117#17117: *7 free rr peer 1 4
2020/09/30 09:56:48 [debug] 17117#17117: *7 finalize http upstream request: 502
2020/09/30 09:56:48 [debug] 17117#17117: *7 finalize http proxy request
2020/09/30 09:56:48 [debug] 17117#17117: *7 SSL_shutdown: 1
2020/09/30 09:56:48 [debug] 17117#17117: *7 close http upstream connection: 13
2020/09/30 09:56:48 [debug] 17117#17117: *7 free: 56DDCC88
2020/09/30 09:56:48 [debug] 17117#17117: *7 free: 56DE47D0, unused: 24
2020/09/30 09:56:48 [debug] 17117#17117: *7 free: 56DE1D50, unused: 56
2020/09/30 09:56:48 [debug] 17117#17117: *7 event timer del: 13: 535061235
2020/09/30 09:56:48 [debug] 17117#17117: *7 reusable connection: 0
2020/09/30 09:56:48 [debug] 17117#17117: *7 http finalize request: 502, "/remoteDesktopGateway/?" a:1, c:1
2020/09/30 09:56:48 [debug] 17117#17117: *7 http special response: 502, "/remoteDesktopGateway/?"
2020/09/30 09:56:48 [debug] 17117#17117: *7 HTTP/1.1 502 Bad Gateway
Server: nginx/1.14.1
Date: Wed, 30 Sep 2020 14:56:48 GMT
Content-Type: text/html
Content-Length: 173
Connection: keep-alive