Would a grounded fat BBL be safe and yield positive results?

I recently watched a video where a surgeon determined liposuction was not an option for a patient and instead chose cut out the fat during a FDL procedure, throw it in a grinder and then reinsert it into the patient for a BBL. My question is whether or not this is a procedure that would be safe and yield positive results and really whether the fat can be separated this way and remain uncontaminated by other tissues.