My father was dx’d with Parkinson’s Disease at around age 90. I suspect that he actually had a closely related condition called Multi System Atrophy, and he died of complications from it at 98.
MSA makes the autonomic nervous system start shutting down. At the end his breathing, his blood pressure, his digestion were all ceasing to work properly. But his mind was clear, he had always been a very intelligent man.
The final week, maybe two, hospice ceased feeding him. There was no point, his body had lost the ability to process food. They gave him water, and morphine to calm anxiety and panic.
So sorry you had to go through that.
My dad got hospitalized at the end. I visited him at the hospital for a few days and then had to fly back across the country to go back to work. He passed away a few days after I last saw him in the hospital. I was always glad I saw him so close to the end, but saddened by not being there at the end.