Welcome.
Guide turning the controller on but not registering that button, I'd look at D27 first, make sure it's on the board. Then all of the traces and such to/from it to Guide and J3p2. Quicker test would be to just swap over a known good top board. If it still has that same no Guide button issue, then it's either some trace to the MCU, or that MCU has an issue. Can also try a firmware update to see if there are any changes.