Hello Ernst and everybody,
Who or what is he serving with his writing of field of occupation? Perhaps there is some self-serving attitude that is interfering with getting in touch with Virgo. Perhaps use Jupiter, once that is reliable then go into Me/Ra/Virgo. When Saturn is with Rahu it's the most feared place, so we need quite a bit of foundation/strength/courage to go there.
Ketu in the 8th is specially hard for men I think, since there is little social acceptance for not being sure about yourself economically, and you are not allowed to (nor by society, but especially your own masculine identity doesn´t allow you) to depend on a woman. It tends to create frustration that someone has to pay for. Self punishment or punishment of the partner. The fact that it´s a hidden house doesn´t make it any easier to understand, accept or deal with.
I would probably start there: explaining that the 8th house IS complicated, and that it´s to a great degree because how secretive it is.
And then Sa/Ra... I have it too. It´s like being a fainting goat: you hop aboard and then fall down again for no evident reason. That can also be shameful and hard to accept, that is: it might help you friend to know that what he has is a real thing. As long as he doesn´t, or you allow him to, use it as an excuse.
Generally I have little hope for pot smokers at that age... / I have the deepest respect for the plant M., I just don´t believe it should be approached to the grandfather fire. /
It´s hard to get more advice not knowing more of the chart, but I agree with Quasar: check for Jupiter helping out. And Mercury for helping Rahu out.
Staffan