Yes... exactly. Nate Grey.
First of all, we have two "Nate Grey" types in DOFP. I guess they are father and son.
There's the chubby child at the beginning of DOFP, listed in the credits as "Mutant Scavenger". I would say that he's 12 years old... you can see him again at the end of the movie, in the revised 2023, running at the Xavier School --- another reason behind the notion that "Logan" is an alternate continuity, because in the 2023 of the Mainstream Universe there are still mutant children and mutants are not extinct at all.
At the beginning of DOFP, when Magneto is giving his big speech, you can see an adult version of Nate Grey among the people; a hooded figure with a white streak among his hair. I guess this is the adult version of the teenage "Nate Grey" seen in "Apocalypse" (1983), among Charles' students. He should/must be the father of the 12 years old "Mutant Scavenger"...
What do you think about it?