eloise With both PAN and Voter ID, I don't think it required providing additional proof of change of name. Just had to link Aadhaar and the rest was pulled from it. I believe it's verified through the fact that both the old and new Aadhaar IDs are the same.
I recommend you get the TG ID in case your gazette notification did not also include a change of gender marker. After that, update your Aadhaar and then using that update everything else (PAN, voter ID, passport). If your Aadhaar is already updated with both your new name and gender markers, you can use the updated Aadhaar to directly update PAN and voter ID; and Aadhaar + gazette notification to update your passport.