I know they at least thought about using a dead ox body for the aliens host, and I think it might've even been in the special edition of Alien3, but what I was talking was if it can really be considered the true if it was only the special edition.
As for the AvP2 runner, you have think about it from a game designer point of view. The only you can be a runner is in multiplayer, so there's 5 opinions you can use when you're in a alien Lifecycle match.
1)create a dog character, which just seems stupid thinking about it.
2)Create NPC dogs all around the maps, which would make becoming a runner too easy.
3)Remove the runner, which would give aliens only 2 classes, which is too little
4) Remove the lifecycle matches, which will make the game MUCH less fun
or 5)Change the rules so the runner can be made by facehugging the corporates, which, though making the game even less of a canon source, does help make the game fun
*sigh* If only I was witty enough to think of something to say here.