Queens are born Queens. We know this. They clearly look like Queens, with multiple limbs and a crown.
We also know that if an Alien can molt into a Queen, egg morphing, and Queens being born Queens, is entirely redundant.
I gave it some thought, and came up with that it's a genetic freak of nature and in no way indicative of what a normal Alien could do under normal circumstances. In a long enough time frame misshaps are going to happens, and that's what the PredAlien is; an abnormality, possibly caused by whatever steroids the Preds used the speed up the life cycle in AvP (yes, I'm accepting that bullshit for the sake of this argument) messing up how an Alien interacts with Pred biology and creating a hermaphroditic freak of nature with a mutated reproductive method.
It's not a Queen, or a drone, but a mix of both which can utilise a hybrid version of the available reproductive methods of both - Egg morphing and egg laying. If it molts throughout the movie, that's part of the f**k up.
There. Problem solved.