Mom's caregivers saw a bulge on right upper abdomen. Urgent Care doctor didn't see but found hiatal hernia on CT scan. Could hernia cause the bulge?

No. A Hiatal hernia is posterior, not anterior. Therefore is not a hiatal hernia.
No . A hiatal hernia would not be visible externally like that. The good thing about her having the CT scan though, is that it would rule out many potentially pathological conditions in that area.
Hiatal hernia. This is a condition in which part of the stomach pushes up through the diaphragm muscle into the thoracic cavity. You can not see this unless you have xray vision. Many people have this, and the most common type is a sliding form.
No. Have Mom Seen by a gen. surgeon who has probably more experience in examination of the abdomine. abd wall eventration would not show up on CT and is probably benign.