You cannot rest in the northeasternmost room in the Rock Bottom.

I tried and I could. Any idea what other conditions could have contributed to this?

I'm not sure. I paid for the room and it wrote "resting not possible here", something like that. I could rest normally in one of the other rooms.

Can anybody else confirm this?

Eraamion, are you still having the same problem?

This is likely the same problem as here. It should be resolved presently.