mabey an extra thin fleece jacket to be worn?
I was thinking the vest be worn under the VB, but over makes more sense.
also my personal experience with winter camping.
I used a 45 degree bag and equinox bivi in 10 degree snow storm under a tarp with an under armor shirt, fleece vest, fleece jacket , and golite wisp. (and thin skipants and cotten pants, on a torso ridgerest, and 3/8" foam under legs) so just adding the vest, in my opinion, will keep RJ warm in his 32 degree bag, at zero degrees, considering, his jacket, vest, bag, pad system, shelter, pant system, head system and VB jacket is warmer than mine was.