UPS loses packages all the time. The envelope was not stolen, it was lost.
Its pretty clear to me its the BANK - they are sitting on the money, and don’t want to give it back.
Not ten minutes ago I was driving behind a FedEx truck with its rear door entirely rolled up and packages slipping and sliding around on the floor.
I agree that the bank is the bad guy, but Canadian law could also have something to with it.