I still believe that the actual cause was tin whiskers, but all the RoHS lobbying buried the evidence.
http://nepp.nasa.gov/whisker/reference/tech_papers/2011-NASA...
im sure that any reasonably charismatic software engineer could scare the shit out of a judge/jury based on code analysis ... perusing the linked nasa document, recurrence odds of this particular failure mode do seem significantly greater than the odds of a cosmic bit flip ...
I'm a very large believer that aggressive RoHS regulations have created more intractable problems than they have solved.