I suppose it's possible, but, man, a horse casting off a cinch is hard to fathom.
I was thinking the same thing. I don’t know how packs are secured to a donkey, but if it’s anything like a saddle cinch I don’t see how the animal could get out of it.
At the end of the video shown, the owner is talking about planning to track him down and remove the packs, but it stops without telling any more.