I don't have experience with your make and model TT. However, even the same make and models can vary since factory installers are free to modify when build circumstances interfere. Here are some suggestions you may have already tried:
Inside the water heater outside door.
Inside and adjacent outside access storage space. My Kodiak Cub heater is next to the front pass through and affords access to the back of heater through a screw on panel.
Inside a cabinet or utility space inside the TT.
Behind a drawer. In a closet.
Inside a screw on panel.
Under a seat.
Etc.
Please don't take offense. I am not trying to insult you. I am sharing my own now humbled experience.
I found out my TT had pass-through lights and stabilizer jack lights when some one suggested to another owner, something simple. Look on the inside of the pass-through just inside the door behind the door frame.
Yes, the salesmen pointed them out to me. Yes I was overwhelmed and forgot. No, the user manual for the TT was not helpful even though I read it end to end.
I wish happy trails too you.