"even if the NWT is accurate--and for all I know, it may well be"
It's not.
BeDuhn's big thing as I recall was John 1:1 and the "a god" translation and he's latched onto the NWT on account of that. He seems to have a real hard on for Jesus being only "a god".
The mistranslations in the NWT go way, way beyond John 1:1 though, and from what I've read from BeDuhn, he ignores them all.
There are some simply brutal translations in the NWT that would not be even conceivable were it not for pre-existing WT doctrine. I can't tell you why BeDuhn seems ignorant of these verses.