If a fumble requires an assessment roll....what happens to the fumbler if the roll is failed?
The get less or incomplete information.
For example, if their Fumble results in dropping their weapon, and they fail the assessment roll, they do not know where the weapon is....
The result should be based on the situation. Since this sort of thing will be happening mostly in combat, this means that they may no realize that they are backing into a friend, or know where their dropped weapon went, etc....