I was looking today at the photos of the unknown Thomas family members whose photos were found in the desk of Charlena Thomas after her death. [You can see them in this article.] There’s no denying a strong family resemblance between one of the men in the photo and the photo of Joel B. Thomas that Suzanne Stendahl sent me.
I don’t think it’s just the mustache. There is a really strong resemblance. If the photo on the right is Warren Thomas (1860-1896), as we have guessed, he and Joel B Thomas (left, 1842-1925) were first cousins, which might explain it.
The other explanation is that it’s actually Joel in the photo as a younger man. If that’s the case it might mean rethinking the identities of the other men in the photos with him.