Hello and welcome to healthcare forum, Jaswinder.
I would advice you to have another radiologist's opinion for your wife's condition, as gall bladder cyst
may occure but it is very rare and can be misdiagnosed in place of diverticulosis
which is common compare to cyst.
Whatever may be the diagnosis from above two conditions, your wife will require laparoscopic cholecystectomy
as the cyst may have neoplastic potential, and the surgery is safe and effective treatment.
Best wishes for your wife's health.