Thank you for the follow up. I'm glad that you called RAINN.
As for the second number you called, did you ask if your call was being recorded? Most places will tell you up front that your call may be recorded. If you weren't told that, chances are that it wasn't recorded.
Yes, doing the right thing isn't always the easy thing to do. However, I'm sure that you would want to see this man put away for years to come. That way, other girls would be spared from his abuse.
It's good that they are making an effort to protect your privacy. But here's food for thought --- even if you can't be anonymous, no one will think badly of you. You were a minor when the abuse occured and it is clear that you were a victim. Even if it happened when you were an adult, no one would blame you. If anything, you would get plenty of support and sympathy.
Good luck to you as you work to put this perv away for years to come!