I don't see any reason why this is "stunning" or a big controversy. It's just a new fossil and they'll argue a bit on where it goes into the taxonomy tree... happens all the time.
The fact is that, as always, those who found it are basically screaming "sensational discovery, mystery XYZ is finally solved", while other scientist are more cautious. It's the old theme of "sensationalism versus business as usual", dangerously close to the stance of attention whores.
Having read the article, I think it's more likely that those weak limbs were used for tree climbing than for grabbing preys and probably this is not a snake but a specimen from some extinct group.