I can't say yay or nay because I've not tried it, however, the ear abscess is a pocket of hardened pus. It seems to me that the pus has to be expressed in order to get rid of it. Maybe the copaiba kills the infection, but then how do you get rid of that pus? It's hard, so can't be resorbed by the body, can it?
I occasionally take in a turtle with ear abscesses. I'll order a bottle of the stuff and give it a try next time.