If I were to do the trip from the washout to McKenzie again it would be down the road to the hunting camp described in the link below and follow the tracks to Belaire.  That would be 4.3 miles to Belaire which would take less time than the 3 miles KF and I did.  I have walked all of the 4.3 mile route and it is all easy walking. Most of it could be done on a ATV which might get past the washout with some long 2X10’s.