Not correct, at least in this context. "Any harm" means there could be no harm, or some harm, but "all harm" admits there was harm. I.e. "any" is not an admis

Not correct, at least in this context. "Any harm" means there could be no harm, or some harm, but "all harm" admits there was harm. I.e. "any" is not an admission of doing harm, or an acceptance that it happened. If you want to apologise, "all harm" admits you caused harm, which seems necessary for an apology. "Any" is a bit like those "I'm sorry if you were offended" non-apologies, though in this case the rest of the message does better than that.