Every time I've asked them for updates they have simply referred to the twitter. I think it's almost certain that they will return all other cryptocurrencies. If their altcoins had been stolen it would have been clearly announced already. Their twitter talks about returning CNY and USD (without a haircut). In the same sentence they reference returning NXT and other altcoins. It's implied that there will be no haircut on altcoins, since 1) they would have been very explicit about it if they planned to do so, 2) they would also mention returning bitcoins since the bitcoins would get a portion of what was cut off from the alts. I guess we might be looking at getting 0% bitcoin back, that's the one thing that sucks.