Best Non-Dairy Substitute for Yogurt in Chicken Marinade

I often come across recipes that call for yogurt in a chicken marinade, but for dietary reasons I need a non-dairy substitute. I have tried using non-dairy sour cream (such as Tofutti), but I found that other marinade flavors often seem trapped in the sour cream when I use it as a 1:1 replacement (perhaps because it's so much thicker than yogurt?). Is there a non-dairy substitute (or mixture of things) that will help keep chicken moist, tenderize it, and convey marinade flavors similar to dairy yogurt?

Thank you!