I used a Rostra kit on my 2021 Ram 3500 with 360 surround view. No problems whatsoever.
I have my tailgate removed and camera is relocated/mounted on rear door of camper at same height as original camera.
I did not remove the camera from my tailgate, but purchased a new one online.
Shouldn’t be a problem removing yours. I left mine in the tailgate for when I want to drop camper and put tailgate back on.