When you bring a new person or group of people into an organization with a certain culture, it’s important to prepare and train them for the culture and what is expected of them. Realize it takes time for people to adapt and there will be hiccups along the way.
At some point, if they are unwilling or unable to adapt, you have to make a change. It might be putting them into a different group or it might mean getting rid of them completely but no one is worth ruining a positive culture.
Sometimes the best way to improve a group is to remove someone from the group. Addition by subtraction is difficult but the alternative can be fatal for an organization.
Have a great day!