Congrats! Now that's something else to make note for customer to be aware. Your hack might work right now, but an upgrade to core code *will* wipe out that hack!
Accept Path info is really an Apache thing ... one standalone (not VPS) on CentOS 6 and 7, for example, has on by default in apache config.
"All of this teaches me that I have to ask A LOT more questions about hosting before I choose my own plan."
Right on target there! Your experience with this has led to more awareness, but just think of the masses of folks who are not IT/Web server persons seeking a 'good' place to host a Moodle. You don't know what you don't know ... and in this case, someone as I just described, would not have a clue as to what to ask!!! :\
Just for grins ... search via Moodle Admin UX for 'slash' to see if there isn't a setting for 'accept path info' in the Moodle? In the Moodle it's called "slash arguments".
Rather than the hack ... go to:
Site administration -> Server -> HTTP
Where one will find:
Use slash arguments slasharguments
'Slash arguments' (using PATH_INFO) is required for SCORM packages and multiple-file resources to display correctly. If your web server doesn't support 'slash arguments' and you are unable to configure it, this setting can be disabled, though it will result in things not working.
Note: The use of 'slash arguments' will be required in future versions of Moodle.
So if that setting (set one way or another will work), suggest un-doing your hack and see if SCORM's play as they should or not.
BTW, there is one other additional way to set on or off .. by adding:
$CFG->slasharguments="1 or 0";
where 1 is on .... and 0 is off.
In the config.php file for the moodle.
If you can get it to work with a setting ... do it that way cause that setting gets retained in the DB for Moodle ... not any code - which will be replaced.