I can see where you're coming from, but I think Yelig-nar bonded to humans in the old days as well, given that in Hessi's Mythica, there was a segment about Yelig-nar and bonding him, with something along the lines of "Curiously, some sources mention swallowing a gemstone to engage in this process," so I believe that combining that with the information that humans would fight on the side of Odium's forces in multiple Desolations, per the Stormfather and the visions Dalinar has.