This has been addressed in another thread. Reposting my response here:
The issue is basically that our site picks up whatever qualities are shown on the Armory. So if they're wrong there, they'll be wrong here. It gets further complicated by the fact that non-battle pets on the Armory show their ITEM quality, not their pet quality. So that makes it even more confusing.
Rest assured, even if what we have showing here for non-battle pets is "wrong", it is wrong for everyone. So everyone is still on equal footing as far as pet score goes.