If they just don't touch the account balances of those who held coins, and give them back a fixed % of that coin, they could probably figure out this situation a lot easier, plus cover fiat users better given how much higher Bitcoin prices are today. For example, with BTC being 57% higher today, I almost expect that they could give ever user 60% of their coin back, and give fiat users 50% of their fiat back. And these ratios should get higher, as long as Bitcoin keeps rising. And in fact, I think fiat users would be happy to accept crypto back too. This would avoid any necessary mass dumping of the coins.
With Bitfinex closing doors to US customers, BTC-e does actually have an opportunity to step back in, even with KYC compliance. But it's really going to rub me wrong way if I get back 7 different coins that do not add up to anything near the claimed 55% of my original Bitcoin.