Thank you for all of the thoughtful and helpful responses to my concerns. I will definitely be taking his picture each morning We have extra luggage tags/lanyard so I might have him keep a card filled out with the room number and my name. I did manage to order a diabetic ID that is not engraved it should be here tomorrow.
I did not realize that the picture ID they take was made available at bars, gift shops andother areas. This would be very helpful if needed. I also forgot about how many cameras are on the ship. I am feeling more at ease but will still be very cautious when we are out and about. As mentioned above the maze to find your way around the ship would be a huge problem and I can see him getting easily confused. He's a very sociable guy and talks to anyone and everyone so he would not be afraid to ask for help.
I don't believe he would attempt to leave the ship without a family member so I'm less concerned about that. I will post an update when we return. I'm hoping for a great cruise and that potential Tropical Storm/Hurricane Lee does not actually turn into a storm We are going to the Bahamas so hoping we will be good.
This board has such valuable information and I sincerely appreciate all of the replies.