Need to add a resource to a project request, or change the requestor.

Hello! 

I need to allow a user to make changes to a submitted project request. In order for the user to do that they need to either be the requester or a resource on the request. 

When I try to add a user as either of those, I am presented with a list of only 19 users, which lacks the user I want to add. I cannot find out what role/permission/group they have in common to have them appear on this list of 19. 

Is there anything you can think of?

Thanks