The Chap was saying this is a Vauxhall problem and that there are other instances of Vivaro’s catching fire (non EV) and he mentioned the recall of the Zafira from fire. Sadly this did not fit the anti EV narrative that Geoff in his Volvo wanted.
Wasn’t that down to a thermal fuse issue in the fan heater blower resistor?
What concerns me though is since the previous issues you list, Vauxhall/Opel has fallen under the Stellantis umbrella and therefore uses Stellantis groups parts tray!
One things for sure though, it wasn’t a battery problem as that is under the front seats.