Sacrificial Heart cannot be found on cruel (Post act 3 completion)

I rushed the last part of cruel Utzaal and Aggorat so i skipped getting the heart forgetting it gave 2 skill points. After I beat the game i went back to farm the heart and complete the quest... only issue is it's not dropping... ive gone from 62-66 in these two zones farming it and its not dropping...

I can confirm that the sacrificial heart does drop in Act 3 Cruel.
I just got it to drop in Utzaal just following campaign.
It may be bugged for you or just simply bad RNG..