[cypher]

I expect you've probably come across the bath idea quite a lot for taming hams but if used at all it's only really suitable for Syrians & even then you must have plenty of things in there for a ham to explore plus a towel in the base, for a Robo or any dwarf ham it is far to overwhelming a space to be in.
I would begin with a small safe area like a plastic box or cardboard box even, big enough to run around in but not too big & make sure your ham can't escape, put lots of toys & interesting things in plus a wheel as most hams will run in the wheel if they get a bit stressed, you can then introduce your hand & get your ham more used to handling in there but take it slow, just a very short period to begin with, alway stop if your ham appears stressed & place him back in the cage with a nice treat.
After such a stressful time in the bath I would give him at least a few days to settle again before trying anything other than just putting your hand in the cage.