In Dimmu Borgir's Progenies of the Great Apocalypse, is Vortex singing 2 or 3 notes at a time?

In Dimmu Borgir's Progenies of the Great Apocalypse, IBC Vortex has a clean vocal section beginning at 2:15. I have been in argument with my fiance for months now as to whether or not there are 3 notes being sung at once. I strongly believe that there are only two notes, the low, louder mixed one and the higher pitched harmonic vocal track over it. She believes there are 3 notes. Please only answer if you know for a fact.