In truth OisE already suspected something, but kept quiet to not arouse suspicion. A thorough analysis was needed but a good hunter values the virtue of patience.
@Angry_Panda
I also thought about this, but didn't find anything clear online (there were some scores were there was a '8' under the treble clef of soprano, alt and tenor).
She knows about this stuff better than I do and did say that I can sing lower if it helps, but I seem to have nailed the high part somehow.
You just gotta imagine yourself as a gospel singer I guess.