I could be wrong, I thought there was discussion of complaints from staff could be held in some of his records for one.
biden gave permission for the senate personnel records to be released, but my somewhat fuzzy understanding is that some privacy law prevented that from happening. i saw some people saying that if reade also consented, they could be released, but i don't know that to be accurate.
biden's senate papers were donated to the u of delaware to be made public after his retirement and he has not consented to have those papers unsealed, but people that seem to know say that there would not be any personnel records in those papers.
the discussion is somewhat moot as reade does not say that she filed a report alleging sexual assault at the time, so there would be nothing directly pertaining to her allegations that could confirm or refute her allegations in any records.