By now people should come to the conclusion that this is totally randomly selected and has nothing to do with your past / current stay record. There are Silvers and Golds received the $30 being reported all over net for example.
For example I got the $50 as Titanium but all my stays since Q4 2018 are point redemption with only 1 pay night this Apr, at a Fairfield JFK. A friend, a Titanium, also has only point redemption the past 6 months, she also got the $50.