I think that the name recognition would be part of the selling point for for her agent, and whichever imprint ended up publishing her fiction. Unless she's a better novelist than I think she's likely to be, I'm not sure she'd sell otherwise. Or that an agent or editor would want to dispense with the name recognition, even if compromised.
I think Hannah Ingram-Moore is a slightly different situation. Besides being a much more egregious fraudster, bluntly, she's not producing anything people want to read/see/consume. (Other than TikTok 'resilience videos', which appear to be largely hatewatched.)
Whereas SW, whatever one thinks of her personal ethics/compromised reputation/writing style/honesty as a memoirist etc, has produced books a lot of people want to read. The gamble for her publishers is, I suppose, whether they will still want to read them, or whether the same readership would want to read fiction by her. (Or fiction that is labelled as fiction!)
Sometimes things don't transfer across genres.
I don't know whether anyone else remembers 'Petite Anglaise', the Paris-based initially-anonymous English blogger who had a big online readership and then got the sack when her employers became aware of her blog and argued that she was bringing their firm into disrepute and working on it during working hours.
She won an unfair dismissal tribunal and got a two book deal from Penguin. I think the memoir sold reasonably, but the novel that followed it tanked.
Sometimes readers used to one genre won't move into another. The whole point of Petite Anglaise was that it was self-revealing, a real-life Bridget Jones, really taking off half days while pretending to have a childcare emergency but really to see a new boyfriend. I suspect the same might be true of the 'Raynor Winn' brand -- that its readers liked it because it purported to be real.