I am requesting some help with a problem that I have banged my head against for a couple of weeks now, while trolling this forum, and others.

I have an Amazon Elastic Cloud Server that is hosting three domains.
I have three virtual host files in the sites-available directory, that are symbolically linked to the sites-enabled directory.
The default, works well, in serving both static html web pages and php.
The second one, I don't care about at the moment.
The third one (I'll generically call domain.com) is our problem child.

It will serve static html just fine, however it will not serve php.
It will also serve html just fine in the alias directory, but the alias directory will not serve php.

I've had several people look into this with no resolution forthcoming.
I've included the virtual host file for reference.

I fully admit that I am far from an expert in this field. I would further say that I am probably overlooking something simple here. That or I don't fully understand some of the concepts involved. That being said, if an explanation could follow some of the proposed changes, I would really appreciate it, because I have been looking over the documentation for nginx and coming up a bit confused. Perhaps a different take on the explanation would help me understand better?