I have had a false call twice, both times they showed up, checked everything that needed checking and called the case unsubstantiated and closed tha case tha same day. But since reporting is anonymous we had no recourse on whoever called.
I was in the middle of adopting my oldest and the calls to CPS actually might have helped, because I cited the CPS coming to my house, and the cases being unsubstantiated and closed. I don't know if the court ever git an in debth report.
So don't worry about the CPS situation too much it is nerve wracking and annoying but in the end no big deal.