“Clearly, the framers did not want divided loyalties otherwise there was no need to exempt themselves.”
What do you mean, exempt themselves from the natural born clause? But there was a very good practical reason for doing so: if they had not, there would have been no president for the first 35 years of U.S. history.
If the clause is so clearly meaningless as you demonstrate, (fence jumper children qualify) why bother exempting themselves.