[cypher]

Bathtub bonding is no different to using a play pen so don't worry about that, is the play pen big enough for you to sit in with him?
Some hams don't like handling much but I do agree you need to get to the stage where you can handle them at least briefly without them getting stressed, I would just persevere with what you're doing, have very brief handling sessions each day & give him some small reward, a treat of some kind each time & he should gradually begin to get more comfortable with it.