Came across this while searching for another topic. Old, old question I know. It looks like, since you hit 20k rep at some point, you were able to delete your answer yourself?
Personally, in this case, I would just recommending editing your answer (which I'm assuming is still the accepted one, even if deleted) to point to the one you feel is a better solution. Something like:
After posting this, [@xyx] (I'm assuming @MikaDo-) posted what I believe is a better solution [link to that answer]. I would recommend following that solution rather than mine because [reason(s) why the other answer is better].
Since the OP of the question hasn't visited the site since then, it's unlikely that the accepted answer will ever changed, but that gives you the ability to "redirect" others to what you believe is the correct answer.
You can, of course, either leave your answer below that as an alternative or just keep it in the edit history.