Do you by any chance have a model number of the AC supply your are using? Seems like it has some sort of protection circuit / current limiter, maybe it is just underrated.
I would like to ask you to take a picture showing the Rocchio’s original power jack’s inner opening next to the one you are using. It is possible that the inner hole of the power jack (into which you have inserted the black meter probe on the first picture) is not making a good contact with the Rachio’s socket (it may be too large). According to @franz’s post (link), the inner diameter of the power plug should be 2.1mm.
Thanks for the great pictures!
Gene