The video seemed to show 26 °C for Extruder 0, which would definitely be a problem.
The other two temperatures looked fine.
The firmware doesn't know your intentions, so it will report any errors it encounters.would it be possible for extruder 0(while not being used in this print) to cause the mintemp?
With those new thermistors, it's time to examine the cables & connectors. A wiggly-jiggly test may reveal something, but it'd be more convincing to dismantle the entire loom and see what's going on inside.