I got the scroll on a Dwarven Fighter and that makes certain things easier - since you're lawful other lawful units like dwarves, are not hostile being key. I almost certainly did the graveyard so I'm 99% certain that you can kill Griff. You have to dig up his grave so it'd be strange to do that without killing him. (Just checked the Wiki - only living dwarves count - even Chaos knights). Basically dont kill random dwarves or kherab and you should be good
I'm fairly sure you're ok to crown but someone will come in who knows more to confirm.
One thing with your routing: make the volcano before you close the gate. Because you need the fire orb to corrupt the heart.
The stone dragons are also insane for item destruction and diminished sight radius makes it extra challenging - good luck.
Completed: All Races, All Classes. Twice.
Fastest Run: Dwarf Mindcrafter - 34803 turns. No wand of tele.
Challenge Games: C- CK (stupid ending), Platinum Girdle x10, Westside Story, Team Teleport - illiterate troll barb, Scroll of Omnipotence obtained
ULE - DE Archer