yea! I found them!
They were not with the trapunto, but it made me more motivated to look harder. Turns out they were in one of the drawers I have thread in, but I missed them the first time as there was some paperwork laying on top at the back of the drawer, and I had not looked underneath.
I always get after my husband to look with his hands and not just his eyes (he never looks underneath anything) and if I'd followed my own advice, I'd have found them a few days ago.