A simple paternity test may answer all remaining questions in this case. The alleged animosity between father and perp versus the friendship between the mother and perp doesn't match well with the friendly terms between mother and father - traditionally, mutual friends only divide after hostile separations, so why the animosity? [Note: however, the money-fan photos open the possibility of drug-dealing rivalry, with one trumping the other]. Given that the friendship vanishes in the proximity of childbirth, and the father publicly distances himself from a bad crowd - and cleans up his own life - the father's statement on Facebook seems telling:
"I'm not the bad guy for not wanting my child around drugaddicted pedo files".
The perp was troubled and allegedly hung a bad crowd. Rumors circulate of a past romance between mother and perp. If there's any truth to these rumors, it might explain everything. That is, the perp may be the daughter's true father; drug addicted and unwittingly thought a pedo by the victim for loving his own daughter. Looking at the Facebook photos, an unrequited, [drug] demented fatherhood might be cause for unbridled jealousy. Even if he is not the real father, he may have reason to think so.
If she was his daughter and he loved her, how/why would he mutilate and kill her?