They will seize all of the thief's assets so even if he sold the BTC there is a chance we might get paid back.
Of course, I am not holding my breath waiting for this to happen.
But in the mean time I am suggesting that any claim on any of the recovered funds will probably involve proving you have the swept or accidentally unfunded coin.
So my suggestion is to keep your coins and do not sell them to all of these people saying they want to buy the silver unless you are aware that you may not be able to make a future claim - the buyer will get any future claim.
Seller beware. Just a thought.