Nice fix Jordan - Matt's solution grips like I don't know what, I can't get it to budge at all. I had to apply a bit of tightening afterwards since I'm too old (and manly) to do two things at once (pull hard and insert) - if you get the time to print a set then do. In my case the belt slipped along its length, rather than sideways (like yours seems to have done), but I guess yours will slip the other way eventually...
Ray
reading this back it looks like I'm putting innuendo into every line, but I'm seriously not