He didn't pay her because she ruined all the tracks she was on.
Ghostface on 50 Cent:
"Yo, this ape needs to stop injecting himself with them stroiods. He's acting up, he better chill out before New York puts his ass on the bench."
Ghostface on Eminem:
"That pilgrim needs to back off. He ain't got no street cred, thats my word."