Archie very well might have red hair. Genetics are much more complicated than the Mendel’s law charts. Just look at Boris Becker and Angela Ermacova (and the idiot had the audacity to ask for a paternity test). Per the eye chart someone posted earlier- it’s absolutely possible that blue+brown eyes bring a green eyed babe. We all carry 3 billions of base pairs in our genom. There is ton of information lying dormant only to suddenly pop up, or being dominant against all odds.
Archie’s looks also may very well change. His eye colour can still change and his hair could get darker. Same goes for his facial features. He looked very much like baby Harry in SA and there was simultaneously a strong resemblance to TM. Some children will resemble on side of the family and than again the other side as they grow, some will be the spitting image of a family member for some time, some have very little to non resemblance to known/living family members. I will definitely wait till his face is all grown before I judge who he really might resemble.
All that said- I wouldn’t put it past them to have posed with a stand-in. But honestly: If they don’t want to show him (which I totally get) then just don’t. It’s one of their best parenting decisions. No stranger has a right to this child just because his parents are seeking the limelight. I hope he can grow up in peace till he makes a decision for himself. I have no clue if his family had any contact via FaceTlme or whatever. Might be, might not be, might be often, might be a rare occasion. It’s the norm for most people living far away from each other, and even for most at the moment. But the only people that „Need“ to see him are the he will have a relationship with.
They could have just released a card without him, a „christmassy“ work of art by him, a picture where you can’t see his face (his hand hanging up an ornament, from behind...). But no, they chose a picture (assuming it really is him) they personally love (and obviously worked for, that is not a candid photo) but deemed unsuitable to use like it is. The whole arrangement and the filter are the epitome of unoriginal.