I doubt he'd have much choice if push came to shove. On the face of things, we would probably have Iridiel and Domhnall sharing a horse, Olan likely needing a horse as well, and then we still have Angora and Jaelnec, neither of whom will be particularly in the mood to slog through the mud and rain to Zerul City. Three horses, five people.
If someone has to go on foot, it'll probably be one or both of the Eireannach.