They might, if needed, if the situation calls for it. As Col. Hood said, the humans are grateful for the Elites' help, but cannot forgive them, nonetheless, for what they did to humanity during the war (pre-Schism).
It's also plausible that another war will errupt between the humans and elites. In Halo: Evolutions there is a particular elite shipmaster looking for purpose for his whole species. At the end of that particular story, he finds it... though what form this purpose took, is unkown.