I believe that he said he will eventually scrap it, but I still wish that he had found a better solution than breaking the hatch glass.
Can't you use a guitar wire to remove the adhesive?
He gets in and out by climbing into the back seat, then into the hatch, and then into the camper, so I feel like properly cutting a hole in the roof would be better.
He hasn't even covered the rest of the hole in the hatch!
I also think that extending the back by a few feet would be preferable, just put a ladder back there that moves out of the way so you can access the hatch, and you can taper the top and sides slightly: