I don't have any source files on this computer, so I can't check myself.
Isn't there a field for a treasure table entry in the root templates or is it only in the actual objects ?
If the field were in the root template, one could generate a root template with such an entry and check if that worked.
However, a summon might despawn instead of getting killed, so it might not work.
The game engine has enough 'black boxes' that can neither be queried nor influenced.
(The henchmen hiring code or the treasure generation code comes to my mind .... ;-)