I think another commenter made a similar point, but I would think yogurt actually helps with browning the chicken. It’s less fatty than mayo, but I’m thinking of mayo slathers that people put on chickens where the fat actually browns more effectively than the straight chicken. If your marinade is super runny, you might have a watery yogurt and can try straining it before making the marinade.

I feel like the move is to fully bake the crust and add the chocolate sauce after it cools like frosting a cake. Otherwise the chocolate just stands too high a risk of burning