Just spitballing here, but couldn't you just remove the hardcoded URLs and let users paste in the Snapchat URL so they'd be breaking the TOS, not you?

Technically, it wouldn't be utilizing their API, it would just be a PHP library for accessing APIs that happen to use their exact API call structure.

I know it's a long shot, and it may not hold up, but I think it's better than just taking it down.