Kalitas doesn't stop sacrifices. All Kalitas does is change where the sacrifice goes from grave to exile. The opponent's Mindbender's Emerge cost was paid (reducing the Emerge cost by 3 down to 2BB) and the opponent would get an Eldrazi Horror token.
Kalitas would still exile the Emissary and give his controller a zombie token.
Also someone has disputed this in the past but can they even pay for the emerge cost if Kalitas in on the board? I want to clear things up, thanks.
Standard: BG Golgari Midrange
Modern: U Merfolk GWUBR 5 Color Humans UBW Esper Gifts GW Bogles
Kalitas would still exile the Emissary and give his controller a zombie token.
Standard: BG Golgari Midrange
Modern: U Merfolk GWUBR 5 Color Humans UBW Esper Gifts GW Bogles