"hacked" = "stealing from your own website"
So they'll pay with the money they stole themselves? At least they got some publicity out of it.
But even if you trust that (just think that they could borrow the money or convert usd to btc specifically for the audit), it's only the BTC part. They have tons of USD deposited too, there's no proof for that.
So there's no definitive proof that any exchange holds all the value it owes to its depositors.