well i guess it's more of a informed guess.
I have my uncle's approved application showing everything in tracker account, even medical shows completed while not required.
one of my friend's refused application shows not available for visa number, expiry date, passport number and country also not available. in his account, medical shows not started, background in progress. the application is closed. the reason for that, i think, is the application being refused at the eligibility processing. so they don't need background finished to waste their Human Recourse. and since this is a refused case, not need to update medical status.
just my guess