Remember aviation is a relatively small community. There is no need to keep an actual list. Example being at my carrier they post a list of potential hires for a few weeks before they offer class dates. Current pilots are encouraged to give feedback(positive or negative) on the potential new hires.

Word spreads fast. If an ahole from your last company gets an interview odds are you will find out via word of mouth and have the opportunity to comment.

You can fool people for 20 mins during an interview but having opinions from people who have flown with them on a 4 day trip is important.