To my knowledge, there are only 2 minifigs who MIGHT be Crusaders that have blue torsos (the Knights from 6067 and 6041). All the other Crusaders have red torsos. Also, apart from the 2 "questionable" ones, no Crusader knight ever wears a black grille helmet. There is ONE that *does* wear a black *helmet*, but it's got a dark gray visor (IE, not the standard one-piece visor helm).
The one in 6067 is (in my mind) amazingly clearly a Black Falcon. He's got no formal affiliation (he carries no shield), but it appears that his shield is supposed to be the Black Falcon shield which is held on the "inside" of the wall, and it also appears that his banner is the lance with a green flag (also a Black Falcon color at the time). Add in the fact that he's got a blue torso, and a black helmet? I'd say Black Falcon. The only reason to suspect that he'd be a Crusader would be that he's in a Crusader set, but that seems like a trifling amount of data to conclude his affiliation-- especially with so much conflicting data.
The one in 6041 is confounding, though. He's clearly got Crusader heraldry on his shield and flag, so there's not much question that he's a Crusader... Except that his torso's blue and his helmet is black, which are staples of Black Falcon fashion! So, he breaks all the rules for Crusader torso color and knight helmet color. I think he lost a bet.