So, someone makes a character, claims a distant (really distant: cousin 9th removed). In practical terms, this means nothing. My 5 greats uncle was the vice president of the CSA. I'm also descended from William Bradford. Does this mean anything practically? Nope(.jpg).
Now, there are plenty of other characters that have interesting relations, minor branches of the Sarum family, for instance.
Backgrounds cannot be vetted. Asking Verone to make a post from some CONCORD official or record keeper from each empire to verify a background is too much.
So, rather than immediately calling them out. "I checked the records, and you're not there" which, in my completely unhumble opinion, counts as godmodding, just go with it. If they start using that relationship for anything other than fluff, i.e. some character says that they're the Empress's favorite niece and, well, we can stop there, by all mean, question that validity. Since, in my completely unhumble opinion, godmodding an NPC, living or dead is bad as well.
If someone wants to do anything regarding a background--and really, what's to stop someone else from saying that "I dug in the records and you were a prostitute as a teenager!"--they should contact the other player first. If someone feels that a background is an issue, make a post here, send a mail, but don't, in my completely unhumble opinion, decide that their version of RP must be wrong and corrected.