Bad hydraulic leak

Your year Tiffin probably has the HWH slide on the Pass rear. I doubt the Slide went all he way out. It probably went out 2 to 4 inches? Is this correct? IF the Hydraulic hose for a slide either leaks or a cylinder leaks the affected room will indeed move out a few inches as it has lost its pressure to stay in. You go outside by the room and have your wife activate the switch for the slide. You will know within a few seconds if that slide has a leak. Hopefully, the leak is external. IF internal, you will see fluid and wetness on the carpet by the inside of the slide by the bed. The "smoke" was probably the fine mist that happens when a hyd leak happens from a very small pinhole. Since your wife stated inside, that probably means you will find oil inside. Doug