Or easily forged and replaced.

[ She's thought of those possibilities, hence asking around. ]

I don't have a clear description of their own necklaces but I wouldn't be surprised if they were blue. [ And since the cult didn't off Alucard with the rest of the poor masses in that pit, she's pretty sure he has an idea what that means. ] Not to mention they apparently have the good fortune to survive life-threatening injuries or be the only one who returns from dangerous missions. So, who knows. Maybe they are knights of Krimnos... or were, in any case.

[ Just not in the here and now. ]