To limit who can see the Team roster on an event by event basis:
  1. Navigate to Fundraising > TeamRaiser
  2. Enter the event name
  3. Click Search
  4. Under the Action column, click Edit
  5. On the left hand navigation pane, select Select Event Options
  6. Under Related Actions, click Edit Advanced Options
  7. Select Define Misc Options
  8. Find Current Team Members Visible in Address Book and Team Roster of Participant
  9. Select the desired configuration from the drop down menu: Yes, No, Captains (Yes means that teammate information is available; No means that teammate information is not available; and Captains means that the information is available in the Address Books and team roster of the Team Captains)

Support can also adjust this for every event with this site data parameter:
Display teammate information in the contact lists of participants and team roster (TRUE means the information is visible; FALSE means it is not visible; and CAPTAINS means that the information is visible only to the Captains and Co-Captains of the team)

There is also this SDP:
Define who can view the contact list information about donors supporting teams with donations. Valid options are: CAPTAINS, CO-CAPTAINS, and MEMBERS. Default is CO-CAPTAINS.

If you are unable to view these Site Settings under the Site Options, Contact Support and reference this article and they can make the changes on your behalf.