It could also be that he isn't as well versed in Alien-lore and decidedly called it a neomorph instead of xenomorph?
Nah. It was deliberate. Like I said, I know that name was used during production.
Perhaps instead of the XENO term (which I am personally not a fan of) we have the Neomorph, essentially the new alien 
It's quite likely. When they were working on Prometheus, they called the Jockey-Burster the Ultramorph. Seems quite likely that neomorph is another new design. Literally says new in the name. lol