About the raging wolvering thing. I don't think much meta-gaming occured hered when it helped out and approached the wolverine. It's not jsut a wolverine going off, its a wolverine with wings, ripping a pack of goblins to shreds. This just screams intelligent creatue in wolverine clothes so much its pathetic. Unless winged wolverines are a normal animal in your worlds.
And yeah maybe the wolverine would attack the new person. But wisdom check DC18 why don't you just say it attacks. How about a spot check, to notice the help in the fight, or a wisdom check DC 7-8. It may be a berserk wolveine but it also has a normal players Int, wis, chr(IIRC it was a reincarnated wolverine) I think it can fairly easily distinguish friend from foe, and notice a helping hand in a fight. And if it can distinguish friend form foe(and nothing in the description says otherwise) it knows when the goblins are dead, and some elf showing up probably isn't an enemy so it should just drop out of the rage IMO.