I'm guessing he backburnered them until (a) he could figure out the magnetic-waves-drives-wearer-crazy problem (or a.5 find out a way to drive them crazy in a way that spends more money on ribbon speakers); and ( concentrating on the speaker thing.
He's probably mulling over the first problem in the back of his mind, but not devoting any intentional clock cycles to it.
Is there an equivalent to the Faraday cage, except for magnetic waves?
I was also considering suggesting to him to try it on a significantly smaller scale, to reduce the problem by sheer scaling down of the cause of the magnetic waves -- say, IEM's, but where the ribbons themselves don't go into the ear. (But you don't want to make them too far from the opening, as I'm sure that will cause its own share of problems, acoustically.)
Sanity check?