Fixing Post Pregnancy Belly After Hernia Repair?

An abdominoplasty procedure is the gold standard for improvement of the abdominal bulge in the picture. Patients benefit from having the excess skin and muscle removed as well as tightening of the abdominal muscles and fascia that are stretched after pregnancy or with age.

Your surgeon is correct.
If surgery is out of the question, try a course of Core strengthening exercise using a Pilates or Yoga technique under the close supervision of a qualified trainer or instructor.
Surgery is likely to yield a 7-9 result on a scale of 1-10 whereas non-surgical methods are only likely to yield a result of 2-5. However, exercise is always a good idea and should you decide to proceed with surgery at a later date, it will only enhance the result.