Having a group of people working on a single Twitter account can not only be a security nightmare because of the shared password, but when a person leaves that group or company, that shared password has to change.
TweetDeck Teams fixes that by letting you make an account accessible to team members without sharing a password with them. There are two account levels – contributors can tweet while admins can add and remove team members as well as tweeting.
Contributors are also restricted to accessing the team account from within Tweetdeck. That should reduce the chances of a personal tweet mistakenly popping up on a company account.
If your company has already shared its Twitter password with a large group of people, you can change that password and revoke app access for the rest of the team. At that point you would start using TweetDeck Teams to manage access to the account.