My 5 year old daughter told me she was molested by her dad. Do I have to let her go visit?

If your child has made an outcry of abuse, you must notify CPS and/or law enforcement (police). You said CPS "dropped the case". CPS normally investigates and makes a finding that a) there's reason to believe abuse occurred, b) the abuse allegation is "ruled out", or c) they are unable to determine whether abuse occurred or not. If CPS has ruled out the allegation or was unable to determine but there is an open criminal case, that may certainly affect her dad's visitation rights under any existing order. You don't say whether there is already an order in place, and that is an important factor affecting his possession and access rights and your ability to relocate with the children. You should contact an experienced family law attorney in your area and schedule a consultation to discuss your rights and what's permissible for you to do under the circumstances.