Not sure if anyone can replicate this. My source files are MOVs, ProRes, 25fps, PAL, with 2 PCM 48kHz mono tracks. The files are linked in Avid via AMA. Premiere is set to import audio as mono (partly because I need to isolate specific speakers and they are recorded split mic on each track).
On import into PPro, two tracks show up in the timeline, but on closer inspection, both tracks are from the first audio track of the QT movie.
Thanks for posting, I have passed along your experience to the right person.