Not sure if that's the plaster body cast of the stunt performer, or Bolaji Badejo? It looks too small, but if it's for the stunt suit, it's sporting the head rest.
Unless, the smaller stunt suit originally did have the head rest - but was removed for Brett's death scene?
No. I don't care about canon. Not really. I take each film as it comes. No point in trying to make sense of everything - you'll only drive yourself insane.
I guess we can be less bothered by a predator that seemingly hunts only dangerous prey. We cannot considerate ourselves dangerous enough on a daily basis to trigger a predator's hunting needs.
Parker, has a light beard throughout the film. Watch the 4K, and you'll also notice Lambert's hairy forearm during the start of the chestburster scene - a nicely-detailed 4K image.