It's just another version of a researching accidentally capturing you in a camera, but much harder to link you to the captured information.
Based on the last 2 years of "show your papers" vaccine cards, I'm not sure why you'd pin this on Republicans.
Once they have a relative, it isn't that difficult to narrow it down to Bob. Think about it, you went from 350 million possible candidates to maybe 50 or less.
Go to the relative and ask them if they have any relatives in or near state X or city Y. That should narrow it down to a handful. And also you can narrow further by gender. Once you find a relative, you can logarithmically cull the search space.
https://en.m.wikipedia.org/wiki/Joseph_James_DeAngelo#Invest...
Video by Veritassium about the case: https://m.youtube.com/watch?v=KT18KJouHWg
Small correction, but an important one:
The ancestry portion of the consumer autosomal DNA testing does not imply genetic relation to another human being. By contrast, the genetic relative matching these tests perform is very accurate because it lines up matching SNPs between your test and others’ tests to determine relation.
https://en.wikipedia.org/wiki/Grim_Sleeper
"Franklin was identified at least in part on familial DNA analysis.[41] Police had found no exact match between DNA found at the crime scenes and any of the profiles in California's DNA profile database, so they searched the database for stored profiles that demonstrated sufficient similarity to allow police to infer a familial relationship. They found similar DNA belonging to Franklin's son, Christopher, who had been convicted of a felony weapons charge in 2008. Christopher was too young to have committed the murders, but the familial DNA match led investigators to look at his father, Lonnie, as the likely perpetrator.[42]"