I agree with you because it is not the lack of information that creates the Holocaust deniers. Rather, as you said it is a "belief" which makes it much more difficult to be change. Yet, what the dispersion of the information I expect do is first, makes some of them at least reconsider their position (even one convert is a victory). Second such an information disclosure is very likely to instigate the rewriting of some of the history (text)books that cover that period of time. What this would hopefully do is to educate children while they are still young and thus, if not prevent at least to restrict the number of potential deniers.
The benefit will be for future generations.