I would take her along (if you can manage all of them) and ask.

Listerine? I've not heard that one!

I use either Oti-Clens or Malacetic. Both from the vet. You should nothave to clean ears daily, even on flop eared breeds!

Let us know what the vet says, even if you decide not to take her in and just ask while you are in there.