This is a very common issue found in VirtualMin
The Suexec command on your system is configured to only run scripts under /var/www, but the Virtualmin base directory is /home. CGI and PHP scripts run as domain owners will not be executed.
To resolve this you will have to recompile apache with /home as a base directory for mod_suexec module. Or, mount /var/www as mount if you want to keep the configuration unchanged.
An alternate solution is to disable “Automatic SuExec directive” under VirtualMin’s System Settings -> Server Template.
This should resolve the issue.