Why are doctors back-peddling on Renuva?

Your question is 180 degrees opposite. It is the patient not being able to afford this very expensive stimulator of fat grpwth. each mixed cc can costs from $600to $900 per, therefore to see effective results the patients usually must spend $10,000+++. So I do not "back peddle.." it is you that expect a small amount would stimulate large fat growth. 

The YouTube videos are Shirley based on doctors promoting their practice and not solely for the purpose of educating patients.  It's either that or it's sponsored by the company who makes the product.  Your own fat is the only way to go for high-volume for transfer.  Trust the doctors you spoke with.  Best, Mats Hagstrom MD 

Yes, the results are what's lacking with the Renuva treatment. Your own fat, harvested properly, will give you the best revision results for your BBL.It's not possible to assess your outcome without photos, but if you are a good candidate for a Brazilian Butt Lift (BBL) revision, the optimal outcomes are achieved with: 1) use of VASER liposuction to harvest the fat, 2) a closed looped system such as Puregraft to process the fat, and 3) strategic micro-packet transplant technique. These three processes have demonstrated over 95% fat graft take. This means that your results will be stable as long as you maintain your weight. As an official VASER trainer, I am routinely referred unhappy BBL patients. One of the most common reasons for disgruntled BBL patients is that patients are not able to accurately communicate their desired buttocks goals to their surgeons.  A buttocks assessment tool can be an invaluable tool to communicate to your surgeon the exact buttocks size and shape you are desiring. A Skype or FaceTime consultation with a BBL specialist can help you get an accurate recommendation and pricing.
Respectfully,
Arian Mowlavi MD,FACS
Realself 100 Hall of Fame Inductee