I count more than 22 principal characters, who doesn't belong?

From watching the film and looking at dozens of articles online, below are the characters who keep cropping up as being part of the "22 lives" that are linked by the events of the film. The trouble with deciding who is definitely in the 22 lies in the fact that the film is a network narrative: all of the characters are linked regardless.

Can anyone shine any light onto how this list can be narrowed down to a definite 22? Maybe there are further criteria I have failed to apply? Thanks!

1. Hotel Manager: Paul (William H. Macy)
2. Doorman: John (Anthony Hopkins)
3. Singer: Virginia (Demi Moore)
4. Beautician: Miriam (Sharon Stone)
5. Bride: Diana (Lindsay Lohan)
6. Groom: William (Elijah Wood)
7. Kitchen Manager: Daryl (Christian Slater)
8. Sous Chef: Edward (Laurence Fishburne)
9/10. Kitchen Workers: Jose and Miguel (Rodriguez and Vargas)
11/12. Switchboard Operators: Angela and Patricia (Graham and Bryant)
13/14. Campaign Volunteers: Cooper and Jimmy (LaBeouf and Geraghty)
15/16: Campaign Managers: Wade and Dwayne (Jackson and Cannon)
17: Drug-dealer: Fisher (Ashton Kutcher)
18. Reporter: Lenka (Svetlana Metkina)
19. Virginia's Husband: Tim (Emilio Estevez)
20. Virginia's Agent: Phil (David Krumholtz)
21: Waitress: Susan (Mary Elizabeth Winstead)
22/23: Campaign Donors: Jack and Samantha (Sheen and Hunt)
24: John's Friend: Nelson (Harry Belafonte)