He can't kill him because he is not a witch anymore, he is not tapped to magic. The same reason it didnt work with Hope early even though her blood from 3 species she couldnt kill Malivore in the end of S1 because her vampire side wasnt activated yet. And Klaus didnt have his witch side at this time.

No. He isn’t a tribrid no matter if he “has all 3 types of blood” which he doesn’t btw. He’s a hybrid nothing more

Can malivore be killed by just mixing a witch, a werewolf, and a vampires blood together. That’s what created him so that’s what should destroy it. Why does it specifically have to be Hope.

The most we can assume is something about her blood is specific to her that none of the other 3 species have

But.... he still has witch blood from his mother whether he tapped into his magic or not. Remember in TO when Papa Tunde had Rebekah in that circle and Hayley's blood was able to break the circle bc the baby was part witch? Well A) A mother's blood and a baby's blood don't cross the placenta and B) Hope wasn't tapped into her power in utero. So that whole thing makes no sense. As a fetus Hope was just a baby with vampire blood, a wolf gene, and witch gene (if she never tapped into the witch side then she wouldn't be a witch now).

He has blood but he didnt tap into magic, it wouldnt work without it. Hope had a blood of 3 species too but it worked only when she tapped into vampire side (and was tapped to all 3 species fully). Until she didnt become fully 3 species it didnt work so it wouldnt work on Klaus for the same reason, because having blood is not enough. You need to be fully 3 species at once like when Hope completed transition.

So how was Hayley's blood able to break Papa Tunde's circle?

I dont know what tell you. Legacies episode showed us that Hope couldnt close the portal because she wasnt fully activated tribrid and her blood didnt kill Malivore until she became fully activated tribrid that mean blood wasnt enough. And if didnt work for Hope it wouldnt work Klaus. How it can work for Klaus if didnt work with Hope? She had 3 blood at that moment but it didnt work, that mean its not enough. It was explained on Legacies.

Her vampire blood heals her and keeps her from getting sick except for the one time on TO when The Hollow got ahold of her. So it's like the show can't make up it's mind if her vamp blood is working or not.