Come on. That's pure speculation with no basis whatsoever. But let's just say PBC moved that money to GRN's accounts. SO? That money doesn't sit in a bag in the corner with Cann's name on it, it get's put to work making them money. Those deposits belong to PBC/GRN and they can move funds into other accounts, investments or loans at will. That's how banks make money.
Look at your trading platform. Do you have a cash balance? Guess where it is? Not in your account, that's for sure. It's been invested somewhere and earning money for them. If you need a withdrawal, it comes from a pool of reserves from all their accounts, not a bag with your name on it.