I saw your previous posts on the 4 daughters and notice that RJ Horace, who knows what is what, has set up an unmerged match. I don't know why the merge hasn't been completed, but the 3 suspicious profiles are orphans.
From a cursory examination, I can see no reason that the other 3 shouldn't be merged into Dennys-3, but as you say, this isn't a case for a cursory examination to suffice.
This is an area where I'd be starting from scratch, so I hope someone (else) more familiar with the family might weigh in.