Hi philanopsis
Sorry - I didn't realise you were the patients mum, I thought you were a physiotherapist. In this case and given the fact that things have progressed a bit, yes I would pursue hands on professional guidance and support rather than advice at a distance.
I take it you are in Singapore. Have you tried contacting the Singapore Physiotherapy Association? Their database of their members may list those who have an interest inscoliosis. or the administrator may be able to email their members to ask who has expertise on your behalf. The sorts of physios involved in this area may be paediatric physios, physios who consult and screen for scoliosis in schools or possibly rehab physios that deal with a younger age group.
http://www.physiotherapy.org.sg/
Best of luck finding somebody