I can't see a reason why an administrator would not be able to correct a typo in a returning team's name. 

My top fundraising team signed up for this year, but, misspelled their team name. I was unable to correct it due to: 

Error: This charitable event already contains a team with the same name. Please enter a unique name for this team.

The options I was given were: delete the registration and have the captain sign up again (poor customer service, IMO); or, make the correction in his previous year's record and break the historical link to his fundraising (bad for us as the NPO).

 https://app.blackbaud.com/support/cases/017585796