I do crock chicken/turkey a lot during the summer for the same anti-heat reasons!
Here's how I do it for a ....
CopyCat Deli Roasted Chicken
I put a bowl. dish or plate upside down in the crock, then set a whole chicken on top.
This lets the juices drain out of the bird, instead of the bird swimming in it!
Add seasonings/herbs to taste, inside or on top.
An onion or two inside the bird works well for flavouring. Also fresh herbs.
Sometimes I pour BBQ sauce overtop.
The veggies stay out til closer to the end of cooking, as they cook up pretty fast and would be mush!