Can she not apply for a job now that her schooling is complete?
Then apply for the next step when it’s time and see what they say? Could be a yes, especially as they can’t point to their own policy. Then move back if that’s unsuccessful.
She is not finished with her schooling - she still has the PhD to go. Right now she has a masters that is pretty much useless here in the job market and that is completely useless in the USA (not considered equivalent to a USA masters) for employment. Brexit would kill any chance of her working in the EU for several years, if ever, and even without Brexit she's not qualified right now enough for what she wants to do if she could work in the EU.
With things as they are, she can't work professionally here, which is what she really needs to be doing. She's still here on the Adult Dependent Child of an EU citizen papers. (She has to have that status to get in-country/EU tuition fees. If she has any income, the Uni funding considers her no longer a dependent and international tuition and fees would kick in. An unseen "Catch 22" as the unis are allowed to interpret the rules as they see fit.) We also are still warned by legal advisors that she should remain dependent to have her be safely in the country as EU, regardless of the EU Settlement Scheme letter saying she can work. If they reverse Brexit, and she was out of status she'd be potentially screwed and subject to deportation.
She's had enough of that - it's been three years of her life she won't get back, waiting to know and just flapping in the breeze as the rules change around her. She seems tremendously relieved now, just having the uncertainty removed. And Brexit can go screw itself. (Further.)
Just being on this tight-wire has taken a toll on her, and having worked at the grocery store for the last year has given her a view of the culture here that she would not have seen had she remained associating only with academics every day. She says it was eye-opening, and she was miserable. So, even if things settled favorably with the work permissions, working here is a non-starter outside of academia or in a job allied with her studies. She is not wanting to go back to being a typist or receptionist at minimum wage and spending the rest of her life just getting by, trying to work herself up the career ladder again - not here, anyway.
Bottom line: although she's admitted to the PhD program here, if they won't fund her there's no reason for her to stay. I could keep her housed and fed, and actually could pay the fees for her (assuming they don't change their minds again and re-classify her as an International student), but she says no. She was thinking that if she didn't get accepted to a program in the USA she would stay and do the funded degree here as a backup, but she has been giving it a lot of thought and looking hard at what getting the degree from here in her present circumstances would do for her, and frankly it's literally almost nothing. She says she'd be better off just going back to the USA and getting any job at all (with a retirement plan and medical insurance).
There is no teaching involved in the doctoral degree here - no classes for her to be taking. She would get no experience teaching classes, either. She would basically be working on her one research project and at the end writing it up. And paying the university fees for three years for being able to have access to the faculty for guidance on the project and to get her final dissertation published. (That would be closing on £20,000 by the end.) That degree program would not give her the education a doctoral program in the USA would do. The academic programs she's applying to in the States are five to six years long (fully funded) and with at least two full years of taught courses involved, plus the opportunity to work on research projects (and publish) and to teach. And that's pretty much the only way to be employable as an academic in the USA - those items are critical. She is hopeful that one of them would accept her. There is one that is exceptionally promising right now, so fingers are crossed they choose her. It may well be that she has to go back and do a two-year masters in the USA to be competitive for those PhD programs, as a lot of them are telling her they favor applicants with masters degrees. (Hers from here doesn't really count as one there - it's like half of one.) She's willing to do that.
So, that's it. She no longer wants to be here - there's no reason for her to be here, and she has a very convincing argument for why she'd be better off (in or out of school) in the USA. She just wants to get on with her life. There's no reason for me to be here if she's not here. I can always move back later, if I wish. She says that unless it was to work in her field, she would have no reason to move back even if she could, unless it was to look after me when I was elderly. Which I do not want her to have to do. So.... I will spend the remaining time here doing all the things I thought I was going to do but never got around to doing. And doing the logistics and research necessary to make this happen. (That'll keep me busy for a while!)
I'm glad I had the chance to live here and experience life here. But it's time for us to go home (or, it will be, when I can properly pay for it).