That would be quite the coincidence for the events to happen on the same trip but be unrelated. Possible though.
The headgasket can be ruled out because that was replaced around 20k miles ago. If the overheating is caused by the cooling system, then it has to be either a closed thermostat or failed water pump.
I'm not meaning to take the thread off topic. If my cat is also bad then I will likely try this cleaning method
