As a fellow flier of single-thrashing-palm-tree types in NI in the 90’s, I am going to file that in the “things that never happened” file.
They flew from “Dungannon to Cappagh”, so they’d either flown all the way there from Aldergrove for the task meaning the pissed pilot had escaped the attention of everybody there before flying, or they were basing out of Dungannon. Having spent many happy hours and days at Dungannon in the 90s I am unsure of which particular pub in the invariably-friendly-and-welcoming-to-British-service-personnel-town the aircrew would have wandered down to and got pissed in of an afternoon.
The jump seat bit is not impossible. The “taking the NVGs off because of the IR countermeasures “ sounds a bit bollocks. They might not work so well for a bit if the flares go off so the operating crew would perhaps need precautions but a jump seat gash pax would not need to do so.