Finished a 4 hours work on the bike.
My friend (electric engineer) and I took the battery out, and examined it.
The negative contactor was stuck. We tried some tapping and than gave it 11v and it was opened.
Battery pack voltage was 310v, so we know the cells themselves are fine.
Reconnecting the battery to the bike made no difference. Completely dead.
Looks like the original 32 error was caused by a stuck contactor, which we released.
Connecting it to the multitool, and resetting the errors caused "something" that made the entire electrical system completely shut down. Reparing the contactor did not cure that.