Do you have POA for Health and welfare and Finance and property? I would suggest that is one of the main priorities while she is still in hospital, but don't say that to the medical staff.Have just spoken to the lead on the discharge team who wanted to send her home today. He said that a care package had been put in place (nobody has told us). I asked about the stairs because they are very steep and since her collapse she has been very dodery. Told that she would be sleeping downstairs. Asked what was to prevent her climbing them but he said that he did not think was an issue.
I have known people to arrange for a solicitor to visit the hospital.
You don't mention if she is on any medication for her dementia. If she definitely has Alzheimer's, as opposed to any other type of dementia, then I'm surprised.
Why not ring her GP and explain the situation and ask for a re-referral to the memory clinic.
One other thing, how good is her eyesight? People with dementia need three times as much light. Maybe improving the lighting in her home would help.
Regarding the care package, I would want to know who her named social worker is and the details of the care package.
Either that, or re-ablement, up to six weeks at a local hospital - that might be a solution.
Ideally, she would have been seen by a physio and an OT before discharge.