Obviously they could just send the 316 BTC back to the address that sent it.
I have to admit I would have kept the coins if I had mined the block, but at least I would not be so sleazy as to make up some lie about verifying people.
That is not a lie. Normally when this happens and a miner is willing to return it,
the miner will first need the owner to sign a message from the address that sent it.
After the owner proves control and a right to those funds, they usually provide a new address to send back the coins.
It is not smart to send the funds back automatically to the address that sent it to you for many different reasons.
At the end of the day, we will see how this plays out. But ultimately, the miner has no obligation to return it.