Your source is: "conspiracy theory" of "friends in China". That alone is sufficient to debunk the theory. But it's a topic worthy of discussion.
Your friends posit a bizarre theory. They think China is pushing silver to its citizens from state owned banks so that the government can later implement an elaborate scheme to confiscate those metals back into state owned banks? The conspiracy defies logic.
The US on the other hand, has a motive to confiscate precious metals. The US is the largest debtor in the history of the world and the US has a history of confiscating precious metals. See FDR. I doubt the US will try it again but it will happen in the US before it ever happens in China.
China is trending wealth building. The US is trending wealth destruction.