Most of the posts here have, quite understandably, commented on the challenges of flying an R44 on instruments in IMC. Difficult though this would be, this is probably the least risky of this pilot's actions. A bigger risk he was subjecting everyone to was that of hitting something en route. Unless the images are very deceptive, there is no way he was flying at MSA in IMC, or anything like - I'd guess more like a height of around 300ft. Total Russian roulette as to whether he hit obstacles such as power lines, trees, hills, en route.
And most crazy of all was how was he going to land safely? I can't believe for one minute he had any idea of the vis and cloudbase at his destination and had any reasonable let down plan. No IMC let down reduces IAS to zero, so either he was clueless on technique here or the airspeed reduced inadvertently as his scan was beaten by stress as he got close to his site, which he'd quite probably know from GPS indication.
Controlling a helicopter in IMC with straightish and levelish flight is one thing. Having the capacity to consider all the other issues such as safe en route heights (think Wales AS355 accident) and how to perform an IMC let down procedure is quite another.