You might want to contact Andre's lawyers before making any refunds and get something in writing from them authorising you to do so and outlining the return process (ie, whether everyone owed money will get a percentage of their account balance paid out as BTC or whether people whose accounts show a BTC balance will be paid out in full and those who had dollar balances will be SOL).
That's a good idea.
Andre, do you have any comment regarding this? I read above that you no longer have lawyers, so I guess it's entirely up to you how you want me to refund the BTC to your customers.
I think your suggestion of using the outdated database backup is unworkable, since that would result in sending the wrong amounts out.