Is it imperative to have lip filler dissolved prior to having braces and jaw surgery?

I had a consultation today with an oral & maxillofacial surgeon to discuss my treatment plan. I have an underdeveloped upper jaw, and my upper teeth are also at an angle. As a child I had an underbite and had braces which has resulted in me having an open bite as an adult. I have a very small top lip and so I have had filler to help this. The surgeon is adamant I need to get this dissolved before they will decide on my treatment plan for braces and surgery. Is this absolutely necessary?