We don't know what the Ba'Ku thought about having others live there, because as was pointed out, nobody asked.
The Son'a themselves didn't want to live there. At the end, as whatsherface herself said, it will take time for the wounds to heal. But they did accept the Son'a back.
No where in the entire movie did any of the Ba'Ku state they didn't want anyone else living there on the planet. They might not want technology in their village, but as for the rest of the planet....nope, nothing like was ever stated.