It doesn’t matter what level she is. Mechanically, the biggest deciding factor is is her level versus the caster’s level (second is “good/bad save”). Domination is cast as a CL 12 spell but it’s the vampire’s HD that determine the DC I believe. A significantly more powerful caster could easily overcome a strong save on a lower level character (Hilyga is at +9, possibly higher but that’s a level 13, 17 wis save I think). We don’t really know whether the vampire in this case is enhanced in any way, but that’s well within the boundaries of possibility. The DC could mean that everyone was at or below a 50% save chance.
The argument that this is bad story telling is a stretch, I think. We’ll have to see how it plays out.
How does her level not matter? Higher level clerics in 3.5 have high Will Saves, and Cleric usually have the highest will save in the party. Her will Save should be between +9 and +11. The DC of the spell is 14 + Durkon* Charisma (which is only 4 points higher than the real Durkon). So, let’s say +16, considering that Roy, with is pitiful +4 Fighter Save, and the low level cleric both made it.
It’s just very unlikely that a cleric would fail her will save. This least he could do would be to hang a lampshade on it.
You have failed to parse what I said, and mis-stated the rules.
Firstly, I said “the biggest deciding factor was her level versus the caster level”. I could have rephrased that slightly and said “DC” and been more accurate but the follow up text makes that clear. But the most important factor here is is not Hilyga’s save but the DC. Mechanically speaking which it must needs be pointed out is only passingly relevant. We will not say “+16” because that’s not what it is.
The actual save DC is 10 + 1/2 vampire hit dice + cha bonus. That’s, at minimum, a 17 DC (14 hit dice for Durkon). With no cha bonus. A +2 (+4 cha from Vampire template = +2 bonus, remember) that’s a 19DC and it could be higher (Durkula could be buffed e.g.). If Hilyga is at +9, that’s a <50% save chance. She does not strike me as the Iron Will type.
Btw, Roy’s save is probably +8. +4 base, +2 wis bonus for 14 wis (min), probably has Iron Will (another +2). His weapon might confer an additional bonus as well, as it’s secretly swanky (if so, I’d expect to hear about it soon). And he could have more wis/protection item that confers saves/etc. Actually I checked his wiki page and he doesn’t have Iron Will (that’s startling) but it doesn’t matter anyway.
Because the mechanics are only loosely relevant anyway.