The key things we know are that NCSoft has a desire to cease support of CoH, and that they have not yet had an offer that would be worth selling the IP for.
We have learned a bit about kibun, which can be useful in re-opening negotiations.
We have this article, which hints that money-on-hand is not going to be persuasive. The implication is that they're looking at future profits. Which closing CoH won't get them, but which not spending money on it might make easier to quantify.
My thought, based on these facts and conjectures, is that if they could secure a portion of CoH's revenue stream for the future but not have to invest in it further out of their own resources, it would be better than a one-time sale or simply shutting it down. This could be accomplished by allowing NCSoft to retain a large partial ownership of the new studio that forms, but have no active ongoing investment therein. It would, however, then be crucial to NOT permit them to have any managerial control, because they want to wash their hands of the costs and, in order for it to succeed, they will have to not be engaging in their standard managerial practices. We need to let the company run on its own, with dividends from the profits being all that NCSoft sees any longer.
I propose, in exchange for dividing the shares that NCSoft will own into two kinds (voting and dividend) and only allowing NCSoft to keep the ones that parcel out profits while leaving the voting shares in control of other investors - perhaps Brian C. himself as the man who is going to head the studio - that NCSoft be permitted a nonexclusive license to use the IP however they like, save that they can't sell it without giving it up, in perpetuity.
That is, they can make CoH products if they want. They can use the images and the like. They are, effectively, the best publisher to use in Asia if Paragon Studios wanted to market something new out there because they have the marketing rights already. But they can't sublet those rights; they can use them, sit on them, or sell them, but if they sell them, the new holder owns them and NCSoft can't use the IP anymore. At the same time, NCSoft can't tell anybody else NOT to use the IP; they only have a licensing right to use. This leaves Paragon free to do whatever they like with the products under the IP, without fear of NCSoft yanking it away.