1 year post op and unhappy with Brazilian butt lift results - should I consider a revision or butt implants? (photos)

I have had 360 lipo /BBL 12 mths ago and and not happy with my results. The projection of my bum is still super flat and I was expecting more definition with my lipo . In total 2 litres of fat was harvested. I am now looking at butt implants . A surgeon has told me that a 2nd round BBL would be enough and assures me I will get the results I'm after .. I have been asked to put atleast 2kg of fat on before the procedure. I need advice I just don't think BBL will be enough?