Yes, other than staff, only the thread creator can change the title of the thread. The thread creator can also change the location of the thread as well.
There is one way to do what you are looking for, but it will require trust and discipline on your parts. You can create a dummy account with your team's username, then (privately) give the login details to the people who would be handling the stewardship of your races.
That way whoever was posting the current race could log in as the team name, then change the thread as needed.
The potential for abuse of that system grows as more people know the login information, so it would have to be a small group of users who trust each other in the team. Any infraction performed by the anonymous shared account would result in it being banned immediately. But if you are careful with it, it should work fine for what you wish to do.