It sounds like something like a piece of a one way valve on the top of the tank broke free and went down the line. I can see in your floor plan that the two sinks and the shower are all back to back in a line. And across the bus is a washer drier hookup. Is the water heater just in front of the back wheel and under the refrigerator on the drivers side?
I would look into cabinets and remove drawers to follow the plumbing as best as you can. Look for a 90 degree bend in the hot side from the water heater. Once you find the closest 90 you'll have to take the fitting off the tubing and see if there is an obstruction in it. I'm betting you'll find this fitting under the kitchen faucet as it seems to be closest to where I think the water heater is.
Have you tried to get hot water out of the washing machine hot faucet? I'll bet there is hot there as whatever obstruction flowed straight through a T fitting that diverted water to the Washer and got lodged in a 90 degree bend on the other side of the bus by the sinks.