I think that was kind of the point, like he barely had any idea how to wear it. He looks like a kid who just tried to put on his Dad's suit lol. Because it was Fett's armor, I think there's a chance, but I wouldn't buy w/o a headsculpt. I'm beyond tired of HT avoiding that for this series that's making them BANK. Just create a goddamn sculpt already.
As far as the rest of the episode, I think a Tusken Raider is a good bet, almost all clothing, little new sculpting except for a couple parts and weapons. I doubt the Gamorrean fighter, would need a new body, and I have zero desire since he was so minimal. I also didn't even like their portrayal, they looked like wrestlers in a mask and not with Gamorrean bodies.
Based on last season and based on the 2 new teases, I swear Disney only shows them 1 episode. If you look at the 1/4 scale prototype, they included the detonator switch on his belt for the explosives to destroy the dragon. They probably couldn't find anything else to include and just did that one, even though he wasn't even the one to push the button.