PHEW!! Still...darn it all, I didn't want to have to resort to AE for this...it's going to complicate everything. Thanks for throwing out that PAR possiblity, though.
The aspect ratio of Title sequences seems to override the aspect ratio the original the footage in some instances (maybe all, I don't know). I found this out a few months ago...I accidentally set my project settings at .9, but my footage was 1.0 (or vice versa, can't recall). After export, everything looked just fine up until the moment the text appeared on screen, at which point its PAR took over and distorted the footage. When the text disappeared, the aspect ratio went back to "normal." Took me awhile to figure out what the heck was going on, thanks to that "now you see me, now you don't" act.
I've also seen Photoshop insist footage is one aspect ratio when it's something else entirely, but I haven't bothered to figure out why (yet).