I really like the Critical Failure state of Recalling Knowledge, but I'm a big improviser. Some people might not be good at coming up with false or incomplete knowledge as I am, especially for a module they bought to do the work for them.
As a suggestion, perhaps when a module asks for a Recall Knowledge check and states what the PC knows on a successful check, maybe you can also include something to tell the player when they critically fail? Not for every single one, but for DCs of 8+level. It would be a lot of added value, and a well-phrased Critical Failure in a module could still move the story along. I know that when I GMed "Rose Street Revenge", my Critical Failures punished the players too harshly; I wish I had given them a wrong fact that moved play forward.