Help Wanted with Missing Track from "We Love the Toho Rmxes!"

Hey there! Recently, I’ve gotten a hold of a box set comprised of 151 tracks on 10 discs in the complete box set of “We Love the Toho Rmxes!” from Iemutsu.

Curiously, every reference I’ve read (vgmdb, thwiki, etc) lists only 150 tracks, and when going through this set, it appears that track 5 from disc 2 is missing. Disc 2 should have 13 tracks, but references only site 12 tracks. I’ve run gap analysis on the disc in question to see if I could find an “extra” track, but to no avail.

Additionally, I’m not sure how exactly references know which track is missing (why is it 5 and not 13 or some other number?) This seems like an oddity, especially considering the track list that accompanies the box set has 151 tracks listed, including the missing track 5 from disc 2 (pictured below).

If anyone else can shed some light on this mystery, please let me know!