I hope it's clear which bits are my words and which are quotes from the report!
Anyway, it's this which is the crunch:
'...risks may include protests at the Library which would disrupt the exhibition and operations more widely, with potential for violence directed towards both staff and visitors, as well as damage to the Library's reputation and relationships with external stakeholders. She told me that she had read the book, and was concerned about accounts of protests, sometimes including violence, witnessed by authors.'
It needs to be very, very clear that the protests at the Library which were anticipated and did materialise from women included: women leaving miniature protest cards; adding copies of the book to the collection; requesting the book; dressing up as a suffragette; holding a read-in; writing complaints.
The protests described in the book include (I expect) trans activists protests, which have been going on for years and include: violent and aggressive threats, extreme noise like banging pots, whistle blowing, high amplification; banging on windows; breaking windows; graffiti; physical attacks and violence; throwing soup, rape and death threats; blocking women's entrance or exit to venues; smoke bombs; harassment; swat targetting, etc.
So the risks the Librarian was concerned about were coming from trans activists. This appears to have been why she has capitulated to the threats. I can't say I blame her, so many women have been subject to threats, and some of them unfortunately have been realised.
It needs to be very, very clear when anyone tries to 'both sides' this, that the risks are not balanced. One side does not protest like the other side.