If as you imply the original chain has been running all these years we can go ahead and refer to it as Lucky Classic and keep on going.
Which, on-topic, translates to if someone steals the NaMeCoin branding those who have or can get the current blockchain and keep it going can simply use the term NaMeCoin Classic and keep right on keeping on.
-MarkM-
EDIT: Remember, money is IOUs so simply not being "above the fold" or "on popular exchanges and aggregator sites" just means the IOUs aka money could be harder to sell to new users, it need not mean they are any harder for their issuers to redeem aka buy back from those to whom they had been issued even if going forward fewer people might be interested in accepting them over again having redeemed them. Its not as if the existing exchanges etc suddenly changed the existing buy offers columns over to suddenly become buy offers backing the newfangled fraudulent version is it?
It had been running for many years until some point when it became untracked.
Well, I'm still not convinced that if my NMC holdings one day would become NMCClassic, while some irrelevant people would parasite on NMC name and history and benefit from fake NMC on pools and exchanges and sell their fake coins to people who would be convinced by them that it's the only one "true" and "revived" Namecoin - that it is a normal way of how crypto works.
Even if NMC is not dormant right now, at some point in future it could face stagnation, when block explorers are not renewed or exchanges delist it if the volume is low, and that could be ideal point for attackers to convince that their NMC (forked, for example, from some point in 2013 before they sold it and had a lot in their wallets) is real, updated NMC, listed by them on pools, cool exchanges, aggregator sites.
The solution could be to recognize this kind of scams and not accept them, be it submitted to CMC or other aggregator sites, or pools, or exchanges. We need serious projects that can investigate the crypto scene, recognize and report fast to community these fraudulent activities, even if they are hidden under a mask of good. Anyway thank you for discussing, long live NMC!