Food options

Do you have a hospice nurse? When my wife was on hospice, her nurse was a great source of information. There was also a 24-hour phone number to call to get hold of an advice nurse.

(My wife was in the hospice due to her not eating when she was in the hospital. I didn't know they had hospice for non-terminal cases also. She got out of hospice about 6 months later.)

Read the most recent studies on the subject. Thickened liquids are now being shown to not really help with Alzheimer’s patients. I think it makes us feel better to think we are doing something, but does not really give the results you expect

This is such a tender and difficult place to be, and the fact that you are already thinking ahead about pureed foods and thickened liquids tells me you are paying very close attention to what his body is telling you even when it is hard to hear. The coughing and the food remaining in his mouth are signs that swallowing is becoming harder for him, and your instinct to move toward safer textures is a loving and protective one, not a step backward. Finger foods have been a wonderful way to honor his independence and his pleasure in eating for as long as that has worked, and that matters enormously. The hospice nurse will be your best guide tomorrow since they can assess his swallowing and suggest a speech therapist if needed, but in the meantime you are not failing him by wondering what comes next. Many families in this same place find that small, frequent offerings of soft or pureed foods, things that still taste good and feel familiar, can keep mealtimes feeling like a moment of connection rather than just a clinical task. You are doing this with so much care, and that love shows in every word you wrote.

I hope these references can help:
https://hopebridge.care/hospice-nutrition-and-feeding-beyond-the-feeding-tube/
https://en.wikipedia.org/wiki/Palliative_care
https://thegeriatricdietitian.com/embracing-hospice-end-of-life-nutrition/

You have my condolences.