By bypassing his group members and going straight to their course professor can cause conflict within his group. This will not only make his team members unhappy but also he may not be able to ask them for any help in the future. He wasn’t being a good group member because he went behind his group members’ back and acted on impulse.
It is not right for TJ to go to his course professor without informing the rest of the group first because even though his group members were nonchalant about the issue he presented, they have no idea how this scenario affected TJ. I agree that everyone should know the severity of plagiarism however there may be some other factors why his everyone responded nonchalantly to his questions about KC. Some of these factors may be that TJ called all of them late at night and they all just want to give him quick