Even with the nicely laid out structure you have above, there is no way that the current data you've provided will support identifying whether someone with the position of "Senior Dev" should be a member of the "Team lead Team1" node or the "Team Lead Team2" node.

Your data needs a "PositionID" and a "ParentPositionID" column to do this task consistently. Please check your original table and see if such things are available. If they aren't, then your team will need to add them either directly to the table or as a sister table. If that can't be done, this project is doomed to failure.

An even more effective alternative to PositionID would be to have EmployeeID (or some such) and a ParentEmployeeID column.

In either case, the PositionID or the EmployeeID must be a unique number to support this task properly.