They are definitely males, and I do not believe they are sex-links. Which could explain why as chicks they looked female to him. (Do you have any photos of them as chicks?)
Until proven otherwise, give him credit for it being a msitake.
Spurs are not a good indicator of gender during the first year. Haul them back to him and tell him you want an exchange for same-age girls, and that you want to pick from the ones he has available. Then pick ones that look feminine, based upon their breed.
This is the only one I can find right now of when they were younger. This was about the age or a little later that I asked him about them, I even sent him pics of the two.
I would ask him how he got his RSLs. If he is breeding an rsl hen to an rsl roo, you are not going to get the sex-linked characteristics. The coloring in the picture you posted above would be correct for a first generation rsl pullet, but that comb is a dead giveaway at that age. I would guess he is breeding his own rsls and not doing it correctly to get the sex-linked color.