I was closing in on my no-hit calling guy too, but after I lit him up he was screeching for his buddies to come running. Sure enough his buddies hit me and I was on my merry way back to the spawn.
I have never seen anyone act like that and I would certainly not play with people doing that.
You role as a responsible player at that point is to adress that fact right away (by having a gentle talk with the player and his 'buddies'), or have a ref adress it by removing the player and informing him about why he is being removed.
there is a strong difference between thinking
you hit someone and then they hide, and 'hosing' people that blatantly don't call the hit.
I have seen many many occurences of the first case and very very few of the second.