As been mentioned, I meant with LE Audio now available on Phonaks new platform you won’t have the excessive battery drain of bluetooth classic.
And to answer
A. Yes could well be possible, but unlikely, get the leakage sorted as best as possible, get custom molds made.
B. No not likely, always best to treat the cause and not the symptoms if possible.
Does the HA kick off if turned on and placed on a flat surface? is it possible to post your audogram.