I know nothing about this specific treatment, but it raises a lot of red flags. They refuse to publish results. This could mean one of 2 possibilities:
The treatment doesn't work - so if they publish results, patients would stop going to them and stop giving them $250,000 a treatment. OR - the treatment does work, and by not sharing the results - they are literally killing thousands of patient a year who could benefit from the treatment, if it really did work. Either way, not good.
If it really worked on pediatric DIPG, it would be simple to prove, since the standard treatments do not do so well.