We were on the Celebration in Feb doing the Red Sea and had a deck 1 outside cabin midship. We could not hear the engine but there was vibration all the time even when in port. It did not matter where you were on the ship i could still feel it even on the top deck in the Horizon bar. I would not let this worry you though it is a great friendly ship with excellent crew, reasonable food and good entertainment and we are going back on board the Celebration 21st March doing the Mediterranean Discovery cruise.
In short YES....if at the stern, engine drone Will be an issue...rule of thumb,higher the cabin.... less nois.
But is it true higher the cabin, more the roll of the ship.