He was a very late 10k registration, or no? After 9/30/21?
What did you put for your registration estimated time?
Typically the cutoff for people having high bib numbers with low estimates comes after the POT cutoff. The cutoff was 9/30/21, so I don't think that's the case. There is someone with a 221xx bib number also in 4:00-4:30 and the lowest 4:30-5:00 I have so far is 230xx. So entirely possible your number makes sense as a 4:00-4:30 runner.
See attached. It's a list of everyone that wants to participate in the list itself. I calculate when you'll arrive to certain places and give tips/info from past year's runDisney experience. It also has meetup information, bathroom information, alcohol information, dark sky for pictures, etc. I'm still working on the final version, but this is the second draft.