What makes you think he is burning that list?
As for your example, you may find it is indeed illegal and you will be liable for the losses if those loses are the result of gross mismanagement and/or if you didnt properly disclose risks to your investors etc.
To clarify my standpoint.
Scamming has to do with ethics.
ethics != law (sometimes it is sometimes it is not)
/GoK
Either way, I dont think you can argue someone would have to break the law to avoid being labeled a scammer. If Nefario does what he (legally) can do to return the assets and bitcoins to their owners, then I fail to see a reason to label him a scammer. Theymos should know better than that, it seems he is just pissed his investment didnt pan out. Tough luck for him, he should have done his own due diligence about the legality of running a security exchange.