'Don’t they screen for that sort of thing, if they do aren‘t they admitting negligence by claiming the disorder was pre-existing, pre-existing sounds pretty much like “we failed to spot it“ to me?'
And have you ever taken a psychology class? There are enough personality disorders that you could probably shove just about anybody into their borders if need be. It doesn't necessarily ahve anything to do with PTSD- rather than saying the patient does not meet PTSD criteria, they government swiftly eliminates the relevance of PTSD in the first place. If the patient has a pre-existing personality disorder, then that's all they need.
And BTW, I don't know what has been done in terms of revising PTSD criteria in the past, but in, say, 2000, with our troops much more adequetely staffed and no major war going on, there is a lack traumatic circumstances to cause PTSD in the first place. The rise in troop infractions for various acting out (i.e., opposing authority figures) would correlate to the wartime situation, which would correlate to an increase in PTSD... i mean, personality disorders.