[six's monkey]

Short answer, not really.
Longer answer, only the combat Owner and the Helper if one has been asked into the combat can receive treasure(s) as reward directly from the combat. Their agreement can be amended, but the c-O determines the moment when running away begins.
Either of those two players -could- enter into side agreements regarding future -trades-. Trades must be made from items in play (not cards in hand).

If I got any of that wrong, or misleadingly, I apologize.