Okay, quick update on the HQ phantom menace screencaps of origins unknown. I was looking around on for more of those HQ TPM screencaps and came across this site: http://ninfo.eu/category/star-wars/
It has all the previous TPM screencaps from fanpop and a lot more, including screencaps from episode 2, 3 and 4. The AOTC screencaps are also much more detailed than the DNRed AOTC blu-ray so I did a little bit of investigating, trying to match up the screencaps to the blu-ray/hdtv transfers.
What I found pretty much seals it for me. Some of these screencaps are impossible to match with the blu-ray or hdtv transfers because they seem to be taken from longer cuts of the same shots. What this leads me to believe is that these are taken from an unedited (or at least less edited) digital intermediate, making it impossible that they are from an actual blu-ray release somewhere. Damn.