A warning at most is what should have happened there. Not a game changing penalty for 2 players just running their mouths at each other 40 yards away from everyone else.
If warnings were already given... and the ref was that hell bent on throwing a flag... they both should have been given off-setting penalties. That would have put them both on notice (cause a 2nd one of those gets you tossed from the game). That's how you get control of 2 players like that without changing the outcome of the game.
Worst call I've seen in a very long time. Absolute crap.