To use TeamLinkt's officials module, you must first have this section enabled by your TeamLinkt Account representative, or you can message firstname.lastname@example.org and request access. (it's free to use by the way, but still in beta-testing)
From there, here's an overview video of exactly how to use the officials section in TeamLinkt:
Important things to note:
There is no import options for referees, they must fill out a registration form with the Type set to Official/Referee
There is no access to the officials module from the team management app
Officials can login and set their availability/view assignments by going to officials.teamlinkt.com and logging in
The Officials module is not on by default, it must be enabled manually by the TeamLinkt team.