that was trivial to fix, actually. and i even remember...
at some point, i brought in the original 1998 mix to do a compare, which meant i had to take the effect off the master (otherwise it would run through the effect) and set the rest of the tracks up to their own fader. i seem to have never put the effect back. i must have accidentally saved this, then forgot about it. those vague memories, right?
putting the effect back on the master got me back where i want to be. i will need to replace this file.