I imagine it would come up eventually as an attempt to get Frank to use him/make him happy. 'I CAN BE USEFUL, I CAN DO THE THING YOU LIKE, LOOK I'M GOOD AT IT'

and Matt might try to backpedal and lie about ever getting actual assignments/going beyond training but Frank is not super convinced

(maybe Frank does a bunch of research after that - because he does verify stuff - and even if he doesn't find out about the murder until later, he gets a pretty good sense what kind of guy Master Robert was)