Suspected emotional conditioning abuse?

Granddaughter father has temp. cust.--I had been allowed to see her and talk to her. Now I am not and don't know why. Daught. is in military camp reserve--he took gd right after she left--hearing is in July. Everything was fine until 3 wks. ago. From some things she said then and last time on phone--I have suspicion they are emotionally abusing her and bribing her before hearing. We live in Ohio--does anyone know what I can do to try and get her interviewed for this abuse? He isn't letting her talk to mother when she calls. He leaves house with kids and stays gone or just doesn't pick up the phone. Sheriff's dept. says I have to have proof not suspicions.