I know I'm not the brightest bulb by any measure, but do some people really take less than at least a few minutes to come up with one-liners for problems as novel as graphical transformations to PDFs? Maybe if the presumed techie hacker / federal worker took it as an amusing challenge I could see this being done, but genuinely out of pure laziness? That's incredible if true.

Hoe big a percentage of FBI / DoJ employees are running linux (with imagemagick) as their work computer? I'd be surprised to see a similar oneliner for a stock windows installation.

Yeah they might have used some web converter, but that on the other hand would have been extremely incompetent handling of the secret data.