Hello @nana59 welcome to connect. It sounds like you are walking that fine line we all feel when caring for someone we love.
My own belief is that you should not feel guilt about the choices others make for themselves. If they don’t want to visit him, then that is a choice they make. His condition makes it unreasonable for him to travel half way across the country, and can you imagine the fiasco of an airport?
I can however make one suggestion regarding the zoom visits. We fit my aunt with a pair of blue tooth aftershokz, that is a bone conduction head set that also allows natural sound. I use them when I do meetings on my computer and they are amazing for the hard of hearing in many cases.
Kudos to you for taking care of him, and putting his need ahead of the wants of others, I know how difficult this is and how much guilt you can feel. Remember, you are one person doing the very best you can for another person and remembering how he was when you first decided to bring him home with you can sometimes help you get through when you have to make the hard choices for him.
How long has your father lived with you? Have the other family members made a visit or looked for ways to help with caring for your dad from a distance?