I tried to fix it by changing the pitch of this part by -1% in Audacity, but it´s hard to find the exact start and end, so it sounded better but still slighty off.
I don´t know why (no technical clue of trackers), but the portamento of 101 seemed to mess up the following note, so I removed it and changed the note.
Also killed the middle part, result sounds nice to me. I hope I dont get run over by a Lotus Esprit.
nemmelheim.de/temp/HERO-QUEST_INGAME.MOD_fixed.flac