The location pictures and maps above point to CFIT in my opinion (and that's all this is). Looks like they were flying low from the Evesham direction in IMC and hit the trees on top of the ridge. The ground rises very steeply just up-track of where the wreckage came to rest.
This does not explain why such an experienced pilot who knew the area was that low in IMC. Simple altimeter mis-reading (would be far from the first time that's been done), or engine problems perhaps?
I still think the wreckage shows every sign of impact with trees before coming to rest in the field. The lack of vertical deformation makes stall / spin unlikely in my opinion.