I'm rather surprised someone would have enough courage to put that up in their resumes... here's a little reading about such things:
Cambridge Who's Who Scam
In short, the 'nomination' simply a scam. Just like about 90% of the "Who's who". As long as the 'participants/meticulously selected candidates' pay (as much as $1000), they can be entered into this 'prestigious' list, which doesn't mean anything. Just random advertisement.
Perhaps they honestly do not know about these lists. I'd hope they do and are just trying to pull a fast one on you (because otherwise, I feel sorry for them). But I'd just dismiss it and ignore such mention, or be highly skeptic about the rest of what's included on their resumes. It's like saying that you are a candidate to win the $1mil prize from Publisher Clearing House (or whatever the correct name is).
Cheers!