1. He would know what a chimera was, and what had happened with the symbol previously (at the festival) but not much more.
2. The royals know of ALASTAIR (if you'll recall, the king sent PCs a letter at the beginning of the mission!) but the general populace do not.
3. If you'll hang tight, we're actually discussing something related to that as I type! I'll reply to you with an answer when I can.