How hard is it for the custodial parent to get supervised visitation ordered on the non-custodial parent?

My husband is the primary caregiver for his 4 year old daughter. The mother's visitation is at times agreed upon by my husband. He has been great with giving her every other weekend, and in the summer he let her stay for 3 day weekends. The mother has married a offender who is still incarcerated. This man has offended a 16 year old when he was 22 and offended another 16 year old at 27. The mother tells my husband that he will just have to "trust her judgement" when it comes to visitation and she will "do her best" to make sure he is not at the house on her weekends. My husband wants her to have supervised visitation at the local Kids Connect. If we can sc up the money for a lawyer again (we are still recovering from the 5k we paid the first attorney) is this going to be hard or easy? Do we need to get our incredibly awesome and incredibly expensive attorney we used the first time or will someone from legal aid be able to prove it up easily? The man will be released from jail 08/2009. Also, the mother has 2 other children and is fearful of us calling CPS on her for the other two being in this situation. She has had 3 CPS strikes against her and says that if she gets another one she will lose her other two for good. One of the two living with her full time is a 9 or 10 year old girl. But, that is a whole different question. Please legal advice, personal experience, anything is welcomed. Thank you so much for your time.