I haven't seen the presentation about the study (a related news briefing is here [1]) so I don't know whether you're correct to say that the researchers haven't shared their methods and data. They seem quite happy to share technical details at the news briefing.
However, regardless of that, I still think it is a good thing if researchers talk about their findings at an early stage, especially if the findings are as dramatic and positive as these. If a treatment is available and you have patients out there dying with no other options, then it is just wrong to hide that away.
In my opinion we treat these things far too cautiously. It is not optimal for the individual and it is not optimal for society. By sharing /and/ opening up options like this to terminally ill patients we can (a) save individual lives and (b) speed up development and refinement of new treatments to benefit everyone.
The problem is that the incentives we have in place treat a cancer death as acceptable, while a treatment-related death is unacceptable for researchers, doctors and drug companies (unless they are shielded by layers of clinical-trial bureaucracy or years of standard practice). The result is that the course of treatment doesn't properly weigh the different sources of risk. Whether the goal is quality-adjusted life years for an individual patient or faster development of effective and safe treatments, the current system is way too conservative.
[1] http://www.eurekalert.org/aaasnewsroom/2016/webcast/?b=38