great advice all around. Clearly this is an excellent, thoughtful, loving Grandpa.
I can only add that my girls were terrified of people in costumes. Easter Bunny, many Disney Characters, Chuck e Cheese was particularly nightmarish. They do get over it, but I might have traumatized them a bit.
Name, normalize, chat with the Elephant, see where grandson is in few weeks.
PS I'm reading this at face value. Reddit has the AM I the xxxxxxx tread, and lots of good learning can come from that. You sir are definitely not.