Well, as long as it's not too obvious and Wolfsbane doesn't have a problem, and the song suits the mission, I say sure.
The game is rated 15+. If you can shoot humans in the head and make them die a bloody death, a couple of HIDDEN four letter words shouldn't hurt.
But that doesn't mean the use of bad language is considered appropriate, just for the sake of it.
But then again, if you can find an edited version... that would be better.