If they sell it and completely relinquish all control over the game and its fate, then they shouldnt worry if the new owners screw up and blow it. NCSoft will have been paid so they shouldn't care, even if their logo is required to remain on it in some capacity such as the login screen.
Except that there's something called the "opportunity cost" that they need to consider. If NCSoft sells the property for a million dollars, and then five years later there's a big nostalgia boom for superhero games and they have the chance to make ten million dollars by releasing a free-to-play turn-based City of Heroes card game for mobile devices, they are really going to regret selling their property and losing nine million dollars in potential profit.
(This is obviously an absurd hypothetical example, please don't derail by getting into the merits of a turn-based CoH game for mobile.)
The point is, NCSoft has to find out what assets the property actually comprises (intellectual property? Code? Logos and trademarks?), the value of the property, determine whether that value is likely to increase, decrease or stay the same, decide whether they can make more money licensing it out or selling it, and determine whether the people they're currently dealing with are the best people out there to make use of the property. That's just the very very very VERY basic outline of the beginnings of a deal, and it would take years even if they were devoting a significant amount of energy. Given that by all accounts, it's the other party who's being aggressive, it's not surprising we haven't heard anything.