Now bathroom light working. Fan on timer. But bedroom lights still won't come on without bathroom switch.
OK, so going back to my very first post!, how many cables are there and what colour wires does each have?
I believe that you have one with brown/black/grey which goes to the fan. I suggest that you ignore that until you have got the lights working correctly.
The other four are all brown/blue, right? (Or maybe not; I can’t see four blue wires in the photos.) I think you identified which one goes to the bathroom light earlier. The other three should be joined together.
So you should have one brown going to the bathroom light in 1way and three browns in COM, and the fan wires not connected. Do that and check that the bathroom light and all the other lights in the house work correctly.
Then we”ll work out the fan.