from that press release, LE (which "could" include FBI, though I personally don't think this is they type of case they get involved in) is reviewing all sorts of social media/FB pages.
This is not a missing person case, a child, an unidentified, nor was she taken over state lines. What grounds would FBI have to get involved?
Honestly, I'm not sure on the validity of that, but I do remember seeing that somewhere. There's been a lot of false info in this case.
I will admit the press release says a private lab though so I might have to agree with you.