When part of your team is remoted, making them cooperate becomes a tricky task. You can see questions like "who is responsible for this" or "why should I answer to him, he is not my boss" rise up. With a remote team it's easy to lose track of some tasks, so strict coordination
is the answer. Someone needs to be in charge of the whole process, revise each person's actions and ensure tasks completion.
Choose one specific channel to maintain ongoing communications
between the team members, like slack
. It will help them ask each other questions and get answers, share knowledge and understand what's going on in the support department. It's also a convenient place to store contact details (skype, phone number, email and anything else you add to your profile).