Sigh it is because of all this planning with another parent that I took the extreme approach. When I take my daughter and god daughter (half sisters) to Disney I just pay for a 2nd room and take their mother and stepfather/father. While expensive it has saved me a ton of heartache on planning.
When I was going to Disney at 13, I was gone in the park the minute we stepped through the gates. Our only connections were via pre-determined meetups.
Anyhow, I think everyone has most everything covered.
Yes, he's spent a great deal of time away with friends, family, members, us, etc. He's travelled as far as Florida with other family members, just not the three of us.