Only thinking out loud, but, if it didn't lose / force out coolant, and didn't boil over, and was still running with no power loss, etc etc etc......
Is there a possibility the temperature sensor was telling porkies (false warning?)
Maybe worth starting it from cold, and comparing the temperatures in the live data to the gauge and the "actual" temperature?
If it were me, from what you've described, I would change the stat, and use the car alone semi locally for a week or so and see how it behaves
You've done the pump, so if you do the stat too - there isn't much left, cooling wise, that will cause significant overheating, save for a big blockage or head / gasket trouble (which seems unlikely with how quick it happened, and how quick you caught it).
As for over 2 hours on the hard shoulder of a motorway, with kids in the car, before being recovered, that stinks