Falling between all the stools, effects of mrONJ, long term at home nursing support needed (but not full time live in)

Hi there. 

Looking for advice on sourcing a bit of (not live in and not full time) nursing care in the home.   Not personal care, but a small amount of daily or very regular assessment and changing of a dressing on a fistula.  This will be needed for the rest of my mother's life (and she isn't terminal, just old!)  The wound is not to be healed, it is needed to drain an infection deep within the jaw which will never clear up.

More detail \:

My mother is in her mid 90s and now in residential care, along with my father.  Mum has seen off breast cancer (mastectomy nearly 30 years ago), a hysterectomy a few years later, and a spinal tumour (secondary to the original breast cancer) about 10 years ago.

She continues to outlive all expectations, which is wonderful of course.  But it does mean she is collecting long term impacts of the cancers and their treatments.

After the spinal tumour, for which they were able to do only a partial surgical removal. she took denusomab for years.  (And is still taking anastrozole.)  

She eventually got one of the common side effects of denusomab, namely mrONJ, medically-related Osteonecrosis of the jaw.  The denusomab had done its job, the spinal tumour was gone (as was a shadow on her collarbone). so we thanked it and said goodbye to it.

Her jaw is badly and extensively necrotic, but she can still eat a reasonably normal diet - and enjoys doing so enormously!  Any surgical intervention carries a high risk of irrevocably destabilising the jaw, possibly resulting in having to wire it up and her having to eat through a straw for the rest of her life.  A prospect she does not welcome.

There is infection deep within the jaw.  A fistula drains the pus, and meeds to remain open as a drain for the pus, as the infection is unresponsive to treatment.  The fisula needs a dressing to contain the pus, which needs changing sometimes every 3 days or so and at times more frequently.

The residential home does not and cannot offer nursing.  

My sister, who lives locally, has been doing these dressings up to now (when they were in their own home and since they moved into residential care.)  She is the only carer for her own husband as well as the local family support for our parents, and we are coming to the conclusion that things cannot continue as they are, it is too much for her.

The District nurses are able to help somewhat, but are too short-staffed to commit to and deliver the regular and timely service needed.  Plus, they are so busy that it is not really realistic to expect them to take the time and care to apply this dressing in a way which does not over time cause damage to the frail skin of this very old lady's neck.  

We have tried unsuccessfully to find a private nursing service which can call in on a daily basis for this one job.  (We have only found private live-in full-time nursing.)  

So we are confronted with a situation where, at this stage just for this one job, we may have to now move my mother into a nursing home.  We've been able to keep my parents (in their mid 90s and totally devoted to each other) together up to now, but Dad already finds the residential care setup very constricting.  He bears it willingly to help his wife and keep her happy but he is simply not ready for a nursing home himself and is very resistant to moving with Mum if she has to move on to the next stage.  Supporting the pair of them in two locations would be even more unsustainable for my sister.   Mum has late onset early stage dementia, so moving her to a situation where Dad is not able to be her constant companion and support would be difficult and upsetting for them both.  

What we would like to find is a way that this dressing can be handled where they are.  We are happy to pay for it but have not found a way of buying that service.

They are in the West Midlands.

Any thoughts or suggestions, anyone?

(x-posted in New to the Community but thought it probably sat here better)