Went quickly through their questions, they seem to discuss exactly the same topic. And they are high on my list of cleanup candidates, merging them into a single tag would help a bit.
I disagree with the merge. Like SnOrfus pointed out in a comment, there are two things to consider: the structure/organization of the team and the relationships between members of the team. However, I think there might be a better tag (or even better tags) than "team" and "teamwork", but I'm not sure what they are at this point. There is, however, a need for tags to differentiate between structuring and organizing a team and working on/with a team as they are very different concepts.
Although, there is another side to the argument. This isn't a site about organizational behavior, social psychology, or sociology. Do we really need to differentiate between these concepts on a site that is ultimately about software development? Perhaps not, and the merge should be the other way: teamwork into team.