If both have Polymorph, the Wizard can turn into anything, the Sorcorer can turn into a horse or a dog, maybe a cow.
Polymorph is a 4th level spell. How do you get to 7th level without seeing anything more dangerous than what you find in a petting zoo? Also, as a noble, he's at least seen falcons, warhorses, and probably pigs. Further, we can reasonably expect he has access to or has seen at least one Summon Monster spell, so you can add everything on that list that isn't templated.
As for the amnesiac wizard... simply because she has lots of knowledge skills does not mean she knows absolutely everything. Traveling a century is NOT a valid reason for knowing 99% of the creatures in my game world. People have spent years in the rain forest and barely scratched the surface of even a small region. Further, some monsters are simply harder to find. About the only advantages she has over changeling boy is she might have more familiarity with umber hulks, hippogriffs, purple worms, and a few varieties of giant. It's very doubtful her knowledge is truly continent-wide if it is to have any depth.
