I just saw WB 12Z JMA update: the 850s do, indeed, stay just <0C at RDU through the entire event and qpf is 0.80”. Based on this, I’m going to retain my educated guess that this is giving RDU ~~6” of mainly wet snow with perhaps a small amount of sleet:
12Z JMA furthest N 850 0C line southern border of Wake county with -1C at RDU: