@Chris ********
gotcha, if you don't have a motorcycle endorsement on your home country's license, then yes you'll need that or a Thai DL to legally drive a scooter/motorcycle which will require the TM30 (and other things).
If your friend refuses they can technically be fined. You could also stay at a hotel for a night and they'll file one for you. That's probably the easiest option (I noticed others mentioned this too)