I just asked a similar question in another thread, but I might as ell continue this dialogue here:
I see people aren't recommending Lugol's inside the ear, but what if it were mixed with some oil?
I quite like the idea of getting Iodine direct to the idea, since it (like many parts of the body) definitely needs it). I alway worry a bit about H2O2 (Hydrogen-Peroxid) as that can also irritate the ears IME, and it's not essential like Iodine is (well, Oxygen is, I suppose).
I like the painting idea, but how do you actually paint? Do you literally use a little brush, or just use a dropper and let drops fall on to the skin? Unless you had someone to help, I can imagine that could be messy.
Perhaps another approach is to temporarily increase the normal internal dose and hope that sufficient would get to the ear in the normal way.