Prank calling is a kids game. You don’t really get any information on them, but at least you are wasting their time and money in the process.
What we do, however, is developing a dialog with the person on the other end until we have gathered just enough evidence to point out whether or not the suspect is a scammer.
As long as you are sure they are scammers and not innocent people, you can prank call them, aswell as post their phone numbers and recordings on the forum.