My primary objection to this question — which is a bit much to hash out in comments, so thanks for posting this here — is that this question blurs the public/private distinction, and does so in a prejudicial and lopsided fashion. To be brutally frank, it is emotional reasoning hiding behind a thin veneer of vacuous empiricism. You could have made the question less lopsided if you'd turned it into a comparative question — asking for evidence for the various accusations against Biden, Trump, and perhaps other political leaders — but making it more balanced in this way would do nothing to resolve the deeper issue.
When I talk about the public/private distinction, I'm pointing out that politics is public matter: ideas, standards, and actions that functionally relate to or affect the state, nation, or individual citizens as a group. When we evaluate a political candidate or leader, we should be looking at policies, agendas, and capabilities. We should not be evaluating the fine details of their private lives. Biden has a single accusation of harassment against him; Trump has a long string of harassment accusations, as well as affairs and interactions with prostitutes; Clinton had that thing with Lewinsky; John F Kennedy supposedly had a fling with Marilyn Monroe... All of this is titillating tabloid material, but it has no relevance to the public political sphere, and won't unless (say) Trump decides to revive the custom of jus primae noctis (which I can totally see him trying to do). It may be unpleasant or disturbing, and it may reflect poorly on the character of the man involved, but it is of no consequence to the administration or leadership of the nation.
Of course, this is the kind of thing that sells papers like the Daily News, precisely because it is titillating innuendo. If it were a decidable fact, it would be dry and boring; everyone's prurient curiosity would be satisfied by knowing the truth, and no one would care. But it is not decidable. The entire debate will boil down to a couple of well-known but boring facts — that Reade filed a minor complaint against Biden, and that Reade's role in the office was shuffled around — and then a bunch or personal anecdotes and recollections that people will believe or dismiss according to their political allegiances. There are no facts here that can be assessed, only innuendos that can be spread. And while I don't agree with all of the moderation standards that are applied on Politics SE, I do get that this forum is not in the business of spreading titillating innuendo.
Part of the problem is that the US political system itself has degraded to a veritable shit-show. The Right has turned character assassination into its primary political activity (starting back in the heyday of good ol' Karl Rove), while the Left has taken a Comedy Central approach to politics, living for that sardonic zing on the other side. In the Trump era in particular, nasty innuendo and sly digs dominate most of our political information, so much so that it's hard to see what's public and private anymore. Everyone goes straight for the groin, because a groin-shot is a money-shot, and the social media universe luuuvs a money-shot. With that in mind, it's understandable that people are confused about what a proper political question looks like.
But we don't want to allow that understandable confusion to drag the shit-show of US politics into the forum.
I don't know why you're so deeply curious about something that may have happened between two people 27 years ago, but even you have to admit that this discussion will never under any circumstances rise above a titillating he-said/she-said drama-trauma of sexual innuendo. The only possible result of asking such questions is to keep the innuendo floating along; to make sure that the innuendo stays in the public eye as long as possible, with the consequent negative emotional impact on the people involved. If that isn't your goal, then you should avoid asking questions like this; if that is your goal, we should prevent you from asking questions like this. Either way, we should all try to stick to things that are politically relevant and publicly verifiable, and leave the dramaturgy to the tabloids.