I personally choose to ignore the "Newborn killed the queen" side of the story, as in my opinion, it wasn't really a fight in the first place. In my eyes, it's equivalent to a mother giving birth to her child, looking at it with love & compassion, & the child pulling out a knife & stabbing her in the heart. I know that may be something of a farfetched (not to mention grim) analogy, but it's the way I view the matter. The queen was cheapshotted, plain & simple.
A fight between the newborn & a predator could depend mostly on what weapons the pred was armed with. An unarmed predator would more than likely fall against the newborn, as it is much larger & stronger. The predator's speed & agility may provide an advantage though. If the predator was armed however, the newborn wouldn't stand a chance. It's slow, sluggish form wouldn't be able to dodge the predator's powerful attacks, & would more than likely end up impaled on the end of a combistick.