As you pointed out, this is identical to @br00no AIP-288 which was rejected 61.89% to 38.11%.
I can’t easily tell the difference between this and that version which he could have re-submitted with the same two month trial as yours.
And so, given the margin of for/against in AIP288 which shows that a good margin don’t like the idea, what makes you believe that this similar version will pass as a trial?
For the record, I believe that shielded/private voting is a good thing to have and for all the reasons in this and AIP-288.