The latter half of Out of the Abyss could be adapted to fit those requirements, I think. Just start with Vizeran DeVir calling for their aid and go from there.
System of choice was voted upon....OD&D and Dungeon World tied 2-2. I am the tie-breaker. Like I don't have enough to do/decide coming up with all this $®©#.
A Paladin in Hell should do the trick.
For what it’s worth, I’d go with OD&D. I recently ran a session using the original system, and while it has its quirks, there was something so very freeing about it – it was fast-paced and simple, no meta-gaming, no power gaming. I even loved the “all weapons do 1d6 damage" rule.