What if the trivial thing was the fella in the coffee shop forgetting to put sugar in that persons morning drink? Should they then be vilified for causing this person to commit suicide? Not targeting this question at you, just a general parallel observation.
Nope, and this is the point, if you go back minute by minute through the last day of someone who committed suicide you can find a negative "encounter", dodgy barrista, train conductor who leaves just as you get to the doors, being rejected when asking someone out, etc, etc.... and placing blame on that person is mental.
Everyone has someone be rude/mean to them, and everyone is rude/mean to someone at some time, the isolated incidents really don't mean anything, persistant harrassement by an individual or group is entirely another thing, and no I don't think the press count in this situation in a short space of time. What if you went back through 6 months, what if the same barrista gave her the wrong drink every other day, is he more to blame? It's her decision to kill herself, there is no logical line from prank call, or a bad coffee, to killing yourself as a sensible response, and trying to draw that line now is even more illogical.
Ultimately if anyone was pressuring her, it was the press being overly invasive, or potentially her fear of them being overly invasive in her life in the future. But its that same over reacting, story generating Daily Mail style reporting that is both hounding the DJ's in Aussie, AND scaring off pathetic advertisers who fear bad publicity(even if its completely made up because reporters are bored of looking for real stories).
If anything its the press over reacting and generating bad public opinion over nothing that could be blamed for both her suicide AND the DJ's losing their job.
The story could have been, "couple wind up merchants make prank call, lol, next story", but instead they decide to make a non event massive news for no particular reason.
Anyway that is all POTENTIALLY a reason she might have been pushed over the edge, it could have been some other incident that day. Maybe a boyfriend, husband, girlfriend told her they were leaving her that morning? Maybe she was being harrassed in work and maybe either the husband or hospital don't really want to go public and so are making an effort to blame someone else... most people do this, because people don't ever want to think of themselves to blame.
Basically I put the chance of her being a completely happy, healthy person who killed herself as a reaction to this call alone at 0.0001%, and the chance of her being desparately unhappy person, who was on the brink of doing it anyway and may well have taken this as the last straw, but not being invited to a party next tuesday, or a guy she liked hooking up with someone else at the work xmas party, being taken as the last straw and killing herself in a week or two should the prank call have not happened was pretty damn high.