The quest rules state that 'If the Overlord won either 'Prison of Khinn' or 'Rite of the Red Dawn' play encounter 2A alse play 2B.

We didn't play either of those quests, does the rule 'Quests that are not played are considered won by the Overlord' also count for this? Or is that only for quest selection?

A quick reply would be welcome, since we are about to play this!

Unless it is actually in the Heirs of Blood rulebook, the "if you didn't play it the OL won it" rule is only for the Shadow Rune when determining finale stuff (or wherever else it is explicitly invoked."

That is, unless there is something telling you otherwise in the Heirs of Blood quest guide: If you didn't play it, no one won it- including the OL.

"The heirs of blood campaign follows many of the same rules for the shadow rune" the following rules list any changes/additions ..."

But the new base game rules don't mention that rule anymore. So we are going to consider them not won I guess

It might be worth a clarification, but I'd bet they would have put "if the OL won... or if it was not played..." if that is what was meant.