I have to guess at a couple of items but in general here it is.
Your husband had visitation and I’m guessing it was only suspended pending the investigation. Regardless, he should go to court with a certified copy of the study absolving him and get the court to order his ex to comply with visitation. If the ex does not comply with that order, he could then file for contempt of court.
Use the Tennessee attorney if you are satisfied with his representation of you. Tennessee courts have jurisdiction over the daughter so a Florida attorney would be of minimal benefit.