One other thing to check .... in 3.6.x there is now a path to php-cli in config of Moodle.
Search site admin menu for path.
Typcially, that path is /usr/bin/php but so far in VPS systems in a user jail (public_html) have found on TMD, LiquidWeb, Host-Ed, and now HostGator ... that is NOT path to the php-cli.
A which php might show /usr/bin/php but turns out that was not the php-cli that's needed.
To find that from ssh as root user type: env [ENTER]
Look for that PATH variable in the output of env command.
I cannot tell you what the path would be ... dependent upon config of cPanel or how WHM does things on VPS systems with different vendors.
Also run, find / -name php [ENTER]
you looking for lines that says/shows /some/path/php
Then run all of those paths with /some/path/php -v [ENTER]
If you don't see (php-cli) in the output of -v then it's the wrong PHP ... it's not the php-cli Moodle is seeking to use.
Go to next /some/path/php -v [ENTER]
The one you find with (php-cli) is the path you want to use in paths of Moodle config.
'spirit of sharing', Ken