This is not quite correct (don´t know, how your GML-team is though) - I´ve talked with my GML team regarding the issue of letting me carry my DC-15X sniper rifle, and when it´s Canon, the only weapon we may carry will be the Hold-out blaster, since it´s the only one in the CRL.
At Semi Canon events it´s the EC that you will need to get an accept from - not all are allowing other weapons though. And at Non Canon you can more or less use everything