Initial Custody Hearing

[Antardom]

I live in NY and am writing in regards to my sister's situation.  Her fiancee has been living with her and her 12 year old daughter for 2 years.  This past June he became very depressed and tried to commit suicide.  Noone was home at the time.
Her fiancee was hospitalized and released.  The evaluating psychiatrist stated that she felt the medication he was on along with the alcohol intensified his feelings of depression and that he posed no harm to himself or anyone else and she felt there was no problem with him moving back home. He was entered into outpatient therapy. However, both he and my sister felt that their living situation was part of the problem and it would be best for him to move out during his recovery and therapy. When he was released from the hospital he did move back home until he was able to move into the apartment he had found.
He was home for a total of 2 weeks during which that time he was not drinking and was going to out patient therapy.  Her ex found out what had happened and filed for temporary custody until an investigation can be done.  His basis for filing was that the fiancee was living there and posed and imminent danger to his daughter. He filed the papers at the time her fiancee was living home.  She was served with the papers 2 weeks after he moved out.  My question is what happens in the initial hearing, and isn't this whole point moot because the so-called danger no longer lives there?