Currently there is not a team version of Twilio in Command. Each agent that wants to use this service will need to purchase their own personal Twilio subscription.
That being said, there is team functionality in SmartPlans that allows you to designate the Rainmaker or primary contact assignee that will send each text step, in a SmartPlan. This allows you to utilize those agent's Twilio account to send those texts. You are also able to use your personal Twilio account to text contacts in either your personal or team account.