I bet when Kendra suggests Anna to drink wine on the weekend, she will suggest that she go to the pool, and of course the old fish will be there. The old fish said that she can only go to the pool on the weekends because then she has the key to the door and without any problem, because then she cleans and fixes something. (Maybe we will get a choice if Anna goes to the pool.) Since Kendra already talked to the old fish after Anna was supposed to meet David and quickly ended her stay at the pool, they have to come with Anna to the pool again and drink wine there with Anna, because she opens up to her requests, and naughty ideas.