[X] The Salloshi will remain safely in Sorcerer's Deep until after the final threat in Sarnath is put to rest.
-[X] You believe he did just what was needed and indeed expected of him, and will credit him for that much, you invite him to accompany you on campaign specifically because you want him to be an informed ruler, one who can speak as honestly with his people as you do with him. This isn't war against a peer, set on a level field with the worst consequence being injury, crippling or death. If he honestly believes he has to prove himself, arm and equip him and place him in the company of some of your less powerful champions. They have a lot of common sense and know when to give battle and when to retreat.
[X] Note that there was the better part of an entire legion kept in reserve, that does not mean their service is somehow lesser nor his willingness to fight discounted