Help 4 a desperate Dad

in despairMaking this as short as possible, I’ve been divorced 5 yrs, ex has custodial custody while we both have joint custody.

However she decided that she wanted to move out of state, I filed my motion to keep my kids here, she filed a motion to have divorce decree modified so as to be able to leave.

I found out Step-Dad has been showering with daughters ages 8, 10, and 11, also ex’s sister is living in home as well with her 4 kids and selling drugs as well as using, this was told to me by my 14 yr old son, who also told me that his mom had shown him and his sisters porn on the internet, social services investigated but said that children were not in danger, and that a “plan” was made to stop Step-Dad from bathing with children and to keep all my kids away from ex’s sister.

However I just file a motion for Permanent Physical custody…..but without the backing of social services and not wanting to pull my kids into court (which might really hurt them) can anyone offer any advice ?? I am in Colorado. TIA