If I understand correctly, the man in the video inserted the plant into a slot in the Ring camera, which allowed him to remove/disable it.
If that's true and he had thoroughly cased the house before, why didn't he bring a little screwdriver or something specifically to do the job? In the video, he doesn't check his pockets or do anything that makes me think he discovered that he was missing something. He just immediately starts looking on the ground for some implement to do the job and obviously he knows that he needs something skinny to fit in the slot on the Ring.
This seems really weird to me and makes me think that he hadn't been in that front entranceway before and wasn't aware that the residence had a Ring.