Do the Pokemon you see in the Battle Maison in Kiloude City get recorded in your pokedex?

Question

I'm assuming no.

Answer 1

The Battle Mansion is like the Battle Facility. It won't record Pokemon you've seen from there. So the short answer: No.

Answer 2

No they don't. It's like Black Tower from black 2,the Pokemon you see there won't be registered.

Source: Experience. I hadn't seen a Mightyena in X and when I battled it in Battle Maison,it wasn't registered.

Hope I helped!