I don't remember where I saw it but there was answer from DVG that you resolve card text if possible. I think it was about evasion or ECM roll when event occured. I'm not sure if it would apply in this case.
Below is question and answer I got in my mind but I can't say if it would apply in this case.
Q: In the event card SAM Sites, who gets to expend the counter? Any plane in the squadron or
the random aircraft being attacked? Can one plane discard multiple counters to negate all the
Can the same aircraft be picked more than once or do they have to be 4 different aircraft?
Does every plane get the bonus 1XP or just the ones involved in the attack?
A: : Any plane can expand. A plane can expend more than one counter.
An aircraft can end up being randomly picked more than once.
All planes present during the Event get the bonus 1XP.