I just worked through the last few FR24 data points. There is no way this was horizontal CFIT. If you extrapolate one more data point, they would have been at 1300 feet and the rising terrain would be at about 1100. Not exactly a generous margin, but six inches is enough! The pictures suggest they did not actually fly into a hillside, though they would have done soon.
BUT... the final recorded speed is 153, 2 knots below Vne (155 according to Wikipedia), So extrapolating for a few seconds they would have been well above Vne. Maybe an S76 pilot on here has some idea of where RBS happens? In any case they were headed down at ~5000 fpm in a steep left bank, not a good starting point.
As others have said, why was he pressing on at 130 in these conditions? Personally in a heli I'd be at walking speed!
Below are the last few FR24 data points - note that the turn rate towards the end is approaching 360 degrees/minute (quick calculation says about 40-45 degree bank). I used them to draw a crude map on top of the topo map:
https://caltopo.com/m/P69T
I know people shouldn't speculate, maybe it was mechanical failure, yadda yadda. But honestly...
-- pilot already knows he's flying close to the limits
-- hill looms up out of the murk
-- oh sh!t!
-- loads of aft cyclic/collective/left cyclic
-- enters cloud, not prepared for a sudden transition to the gauges
-- loses it
Time Lat Long Alt V Hdg
2020-01-26T17:44:13Z N72EX 34.149902,-118.664902 1250 130 258
2020-01-26T17:44:39Z N72EX 34.151505,-118.684235 1250 131 278
2020-01-26T17:44:49Z N72EX 34.151321,-118.691078 1525 118 257
2020-01-26T17:45:00Z N72EX 34.148861,-118.697037 1750 115 233
2020-01-26T17:45:08Z N72EX 34.145741,-118.701096 1950 111 225
2020-01-26T17:45:15Z N72EX 34.143040,-118.703323 2125 110 207
2020-01-26T17:45:23Z N72EX 34.138824,-118.703407 2050 127 163
2020-01-26T17:45:29Z N72EX 34.135498,-118.699608 1700 153 120