Does a character need to be in the challenge during resolution to satisfy this or can they have been removed (Toll Gate, Field Spikes ect.)

A character has to be present during the resolution of the challenge in order to be a participating character.

In support of that assertion:

(3.31) “Participated” and
Removal From Challenge
A character is only considered to have participated
if they remain in the challenge through
its resolution. If they are removed from a
challenge, there is no memory of that character
having participated in that challenge.