Can a Doctor Perform a Panniculectomy but Also Tighten Muscles?

Hi there-
I think you are thinking too much about this, and starting to fall into a trap I see too often- where a patient doesn't like what a surgeon told them, so they start looking for a surgeon who will tell them what they want to hear...
Nothing good will come of this...
It sound like you need a tummy tuck. There are many variations (I personally do 4 different types of tummy tucks), but the operation best for you will depend on many variables and a consultation would be necessary to make recommendations.
Your best bet is to find a surgeon certified by The American Board of Plastic Surgery that you like and trust and follow their recommendations.
If you wave a bit of money in the air, you will find someone to do what you want- but it's your body and safety we're talking about!
Here's some advice on how to find a surgeon you like and can trust:

Without photos and an examination, it is difficult to provide specific recommendations.
A panniculectomy primarily removes excess skin, especially in the lower abdomen, but it doesn't address muscle separation or upper abdominal skin laxity. If you're only concerned about the skin below the belly button and don’t have excess skin above it, a panniculectomy might be sufficient.
On the other hand, a full tummy tuck (abdominoplasty) removes skin, tightens muscle separation (diastasis recti), and repositions the belly button, making it ideal for patients seeking a flatter, more contoured stomach after pregnancy or weight loss. The tummy tuck addresses both upper and lower abdominal excess, and is often combined with flank liposuction as well to improve contouring.
It is important to consult with an experienced plastic surgeon who can customize your surgical plan and determine the best technique for you based on your individual anatomy and goals.
Krishna Vyas, MD, PhD, MHSHarvard, Hopkins, and Mayo Clinic Trained Aesthetic Plastic SurgeonNew York, New York

Hello,
Thank you for your question. Whether tightening of the upper abdominal muscles with a panniculectomy is technically possible (yes) and whether it is the best option for you are questions with two different answers. 
Without a physical examination or speaking with your surgeons, I cannot know their reasoning for recommending the panniculectomy vs tummy tuck. I do know it is human nature for surgeons tend to recommend the procedures they are most comfortable performing.
The majority of mothers I treat for excess skin and diastasis recti benefit from a tummy tuck (aka abdominoplasty) rather than panniculectomy. This approach allows for full tightening of the abdominal muscles, removal of excess tissue, and repositioning of the belly button. This allows for optimal contouring over panniculectomy alone.
Best wishes,
Dr. Moein