Keen is set up on a filter system that the reader has the option of reading with you or not. I don't believe they see who you've read with or how often, but they are aware if you don't always leave a rating or if you rate low often or high often. They can filter on their end to know if they want to read with you.
The basher list outside of Keen is just some total bs. It's a bitter reader who isn't as popular as they would like to be and have wasted so much time making a list of people who they disapprove of and the way they rate the reader. Readers believe they are next to god (snort) and want to receive a five-star rating from every client, which is not only ridiculous, it's not even logical considering they can't possibly connect with every caller.
I seriously doubt they search the basher list before deciding if they are going to block you or not.