I'll be frank - I am skeptical that any therapy that is purported to cure or significantly affect hundreds of different and essentially unrelated conditions has any more than a placebo (or, at best negligible) effect, particularly when risk is considered.
With an autologous stem cell donation, risk/benefit is one major question, but the second is if the BM stem cells are going to be of that much benefit, why have they not already fixed the "problem" since they have been in the body all along?
Call me a doubting Thomas, but that is just my view. It is personal - but for example, I see children with the same condition as Bee and DS, who were at the same point medically several years ago, but have had MASSIVE and intense medical intervention (comparatively, we are quite hands off) and they are almost categorically doing more poorly than Bee is. In the US, treatment is broad, sweeping and intense, in Canada, it is very much "arm's length" until problems arise, then quite conservative. The prognosis is better and death rate is lower.
Furthermore, it is impossible to do a controlled, randomised double blind study for treatment like this. The diagnosis for autism on the rise, partially since more is "recognised" as autism now - not just the "classic" autism of only a generation ago. As a result, there is not as much data on the long term growth and development of those with "more functional" places on the spectrum. Is it possible that the beneficial effect of the treatment is not related to the treatment at all, but the intensive therapy that occurs at the same time, or just through time and biology. Not all "autisms" have the same root cause - my family's, for example, is a spinoff of mitochondrial encephalomyopathy - but to think that one treatment could fix them all is akin to saying that one drug will cure all cancers, regardless of type.
Donning my flameproof knickers - this might be a rough ride...