Would it be possible to VPN to an EU address and download? Or travel to the EU and download this software?

I’m sorry, never supposed to touch autopilot? Under any circumstances? Other than that, yeah, 100% if it detects you are not paying attention via wheel nag or eye-tracking camera at all it will alarm and disengage, potentially banning the user for a short time from using it. They do make it very clear of this result.

If the car was backing out, that was a human driver in control, not autopilot. Autopilot can only be enabled while driving on a well-marked roadway. The first part is plausible however. Likely the software at the time could not handle rain appropriately and you are absolutely right to question this if they tell you it was normal.