What does Ramotswe discover Badule received from Makutsi that leaves him happy?

Ramotswe arranges for a meeting between Carla and Mrs. Curtin, so Mrs. Curtin can obtain closure in her son's death and meet her grandson. She did not have to do this. She could just have provided the details given by Dr. Ranta, but she truly wanted to help Mrs. Curtin and Carla.