Hi Faye,
Sorry this post is all jumbled but in a hurry to go out. Some comments may be relevant, others not.
If they are saying your dad ready for discharge they will probably be classing him as (described in a horrible term) a ‘bedblocker’, which means hospital will be getting charged daily for his bed. This is NOT your problem though but theirs. The main thing about any care supplied is that your dad is safe. As much as you want him home, and so does he, if an unsatisfactory care package in place, this leaves door open to all sorts of further problems in the future.
Does the hospital have a rehabilitation ward that your dad might benefit from whilst investigations continue about his future?
Would a temporary respite stay in a nursing home be worth considering? This would need be in writing.
You have a right to be there if a mental capacity assessment is done on your dad.
His doctor/consultant can advise on whether he needs residential care/EMI residential/EMI nursing care. Lists of places can be supplied by local soc services. They should include details of what each home is registered as. I was given a list of 33 places, and yet there was only 5 that would meet hubbys needs. Even when you look at any, staff will then visit your dad and go through his care records to ensure they can meet his needs and have the relevant staff.
Advocacy has been mentioned by other members and is available from variety of places, depending on cutbacks. Our choices in this area are getting less.
Try a local carers group to see if they offer the service.
Contact your Healthwatch for your dads area.
CarersUK have a helpline, details here Get in touch with us | Carers UK
Enquire if your hospital have a PALS service. Explanation here What is PALS (Patient Advice and Liaison Service)? - NHS
As you have already contacted the CEO at the hospital, you may want to consider taking it higher and contacting the Secretary of State, Matt Hancock Contact Matt | Matt Hancock
Not sure if you already do this but I know other members on here do it, and that is keep a form of diary. Keep copies of all letters, emails sent. No matter how many times you share something, always keep a copy for your own records.
Make a note of all phone calls, ensure you get the name of the person you speak to. Write down dates and times. Same goes for conversations held with staff at the hospital, Write a summary of the event as soon as you can or even during any meetings.
Any formal meetings there should be minutes, request a copy as is your right. When you are alone among several ‘professionals’ not easy to remember all the names or roles. If any such meeting opens and no minutes seem to be getting done, request it. The sad thing is it’s like building a case for the future, if ever needed. Plus if it comes to even more formal complaints, the more info you can give the better.
Whilst your dads care and safety will be uppermost for you, remember you need time for you too. Use the forum to offload. Whilst all our situations are unique to each of us, many of the emotions and problems faced are the same. We wont walk in front of you or behind you but right alongside you.
Good luck and hope some of my waffling makes sense

x x