Not wanting your husband to visit his parents with his child while you’re not there is a whole other level of control. How anyone can’t see this is baffling.
To me, visiting implies a few hours. This is staying. MiL tries to take over when OP and DP visit, but DP doesn't like to say anything to her in case it upsets her. That all suggests that MiL will be in charge. She has already put DD in a bath where the water was too hot.
You can't say that the OP is being unreasonable to have some worries. Whether or not you think she should overcome those worries is a another thing and down to personal perspective.
But when you put those worries with a first time mum, leaving the baby for the first time, a baby who needs her mum to settle her at night, I think it's understandable that the OP is anxious. Wanting to minimise the anxiety is also understandable, so thinking that she's rather the DD was at home in her own bed is a logical conclusion to that. I don't think she needs to be slated to this extent for thinking it.
However, OP try to let it go. DP takes DD to his parents for the weekend. Trust him, and go away and enjoy yourself as much as you can. The probability of anything serious happening to her is vanishingly small, even if things aren't done exactly your way. Then when you're back you can talk through with him how it actually went, rather than basing your conversation on what ifs, to decide together whether it worked or not.