Dolphin 7.1.2 Installation Error

I have a dedicated sever (Ubuntu) running NGINX. I have 2 Dolphin sites. I set up both vhosts exactly the same - only changing the respective domain name for each host configuration - and the first site loads correctly allowing me to install Dolphin; however, the 2nd site gives me a 404 error when I attempt to install Dolphin via the installation link (domainname/install/index.php). I have both vhost set up to run off of the same IP address (not the server's IP:-)). When I go to the domain name without the /install/index.php added, it states VHOST successfully created. When I attempt to install Dolphin on the 2nd site and navigate to the /install/index.php link, I get 404 ERROR. Any ideas on how I can fix this?