So you cleaned everything off, G1 and RainX and it was ok? Perhaps that's your answer.
I had similar issue last year. I cleaned everything off the glass using various things including vinegar, but the wiper judder persisted. So, like you I switched to Bosch aero blades (excellent) and all was good until I applied the RainX again. Now I just leave the front windscreen clear of everything and have had no further problems.