I've had a look around for a bit and cant find anything on the matter, only that gametracker can take a while to record stats (around a few days at most) but nothing about profiles not saving.
I recommend you take a look on
their help forums in case you can find something that I've probably missed.
As long as people are aware of this problem and see you actively in game a lot then you might be able to not rely on it as much as necessary, if applying for staff, because people will know you to be an active member of the community however the definitive proof sure would help.
Sorry I couldn't find a definitive answer for you though :/