Wrzlprmft's answer is spot on. I'd like to add that, in a larger sense, we should assume that question askers are (1) adult professionals, who are (2) basically familiar with academia at the level of a prospective graduate student or higher, and are (3) asking for quasi-technical answers. In about 95% of cases, questions for which any of these these assumptions are not true should be closed.
As such, answers like "Disclose for your own benefit. Sleep well at night." are at best unnecessary and at worst patronizing. We can assume that OP, as an adult professional in academia, already knows that lying is bad. What they're actually asking, though, is very reasonable: is it possible to avoid disclosing the incident without being dishonest? This is the quasi-technical question that's being asked; any answer that does not address this question, based on references or personal experience in academia, is non-responsive. (You could argue that you were challenging an incorrect premise in the question, but such "frame challenges" must "respect the asker, in particular their expertise, privacy, and problems.").
I recommend keeping this in mind for future, otherwise you will likely continue to have a bad experience here. For example, this answer contained many "life lessons" such as quotes from the Bible, French proverbs, and ending with the statement that "we are human." But the asker was looking for academic advice about the standards for peer review, so your answer was received rather poorly. I believe your answer was really well-intentioned, and I regret that it was received so poorly -- but ultimately, most competent adults do not like getting "words of wisdom" when they wanted an answer to an objective question.