Water in reversing camera

Anyone had luck with a 'waterproof' reversing camera.
I use mine mainly to line up the Treg Hitch with the Van .

My first one got condensation in it after I washed the car (rare event) so I bought a new more expensive one that was advertised as "waterproof" and even sealed it with Liquid Insulation tape around the joint, cable entry & screw holes.

Washed car this morning & got condensation inside again, Must be getting in around the lens. using a heatgun to dry it out makes matters worse as there is no where for moisture to go, It gets in but cant get out.

Pulled apart & Bolw waved & dried out put back together, This time will liquid tape around lens If I ca hold my hand steady enough. Wont wash car again .

any answers, thanks ..don