Don't get yourself work up reading about the worst things than can happen. Look for the thing that it is most likely to be. The most common cause of an ill defined shadow on a sonogram is biliary sludge, which is a micro-crystallised layer of super saturated bile.
Did the technician mention "sludge" and do you remember if they measured the diameter of the bile duct?
Gallbladder problems are nearly always a symptom of the liver, usually congestion.
Try to think logically and convince your wife to Liver Flush her problem away. I am sure you won't be sorry.
I am worried that the medical people will worry you to make a decision that you may later regret.