If there is a dental department or a dental hospital nearby the treatment there will be free.
DH had to have treatment which the dentist could not do and was sent to the dental hospital where he did not have to pay. Emergency treatment will be free of charge for this lady; she may have to fill in forms but will get assistance to do so Is she living in a hostel? There will be people there who can advise her.
Jalima, the link you listed is for asylum seeker dentists rather than dental services for asylum seekers.
Lily65, if you haven’t already done so, it might be worth ringing 111 and asking about the emergency dentistry services provided by the NHS. I don’t know whether your asylum seeker lady would be eligible but I’d certainly ring and find out. Ask if not them, then who?
Not me, Somebody I came across, an asylum seeker. She pointed to her lower jaw which was swollen. I thought she was telling me she had a serious health issue. It turns out she needs dental work.
She has no money and is not allowed to work to make any.