A CoolSculpting treatment should not be performed over an area where there is a hernia. It is not a problem to have CoolSculpting performed in a patient with diverticulitis.
Since a hernia is where bowel is pushing through a tear in the abdominal wall, it is best to not treat over a hernia. The risk is freezing bowel which can lead to bowel necrosis. Diverticulitis is no problem.