My question involves a child custody case from the State of: Wisconsin
My daughters father has a sex offense charge that is supposed to be cleared from his record in 2013. Though I do not know the nature of the charge, what I am almost certain of is that he molested two kids, age 4 and 6, when he was 12. Since the offense happened when he was a minor he is not required to register as a sex offendor. Hence the reason why I was unaware of the sex offense charge until about a year ago. My daughter is now 16 months and he is trying to file for joint custody to avoid paying child support even though he has not had any interraction with her in the past.
He has one drug conviction that he served time for, and one felony drug charge that is pending. He also quit his job to avoid paying child support a week before she was born and said he would not have anything to do with her if I filed for child support. A year ago he also proposed babysitting her in exchange for money.
A guardian ad litem has already been appointed but I need to know if Wisconsin Law will allow my daughter to be around him because of his history with sex offense and drug charges.
My questions are:
Is he able to avoid paying child support if he files for joint custody under Wisconsin law?
Is there any possibility of me getting full custody/placement with no visitation rights for him because of his sex offense charge?

