I've had very few bad "trips" but I can't imagine how bad it could be if you know you are dying.
Knowing you're dying can be a bad trip, no drugs required. Someone who's looped their fear until their soul is crushed isn't in much danger - they've already hit bottom.
Knowing you're going to die is a terrible burden, but it presents you the opportunity to choose the last memories your friends and family will have of you. They can remember you living your last weeks in fear and dying terrified, or you spending some time recalling the good times, and perhaps forgiving some of the bad ones. That's all the control you have left of your legacy, and you don't have much time to take advantage of it.
LSD, especially low* doses with someone to help guide can sometimes give people a new perspective. If they can relax their fixation on the fact that their time is up they may see the bigger picture - that we're all mortal, that life is a cycle, and that this is just a part of it. It may give you the opportunity to make your peace with the world. And if not, you're dead anyway. So why not?
* There's adequate margin between free-association, preconception-questioning levels and moon-howling-naked.
sooo many people jump to the conclusions therapeutic doses are same as recreational, finally someone with a clue, wish I had mod points. The therapeutic doses are often barely noticable compared to rec ones