I operate a small commercial brewery and have a little land for gardening. Most of my spent grain goes to a farm to feed livestock, while I always take a few buckets of spent grain home to turbo-charge the compost. It breaks down so hot!! We mix it thoroughly with horse stable straw to promote aeration and increase carbon content - I understand a smelly heap is carbon deficient and sheds nitrogen as stinky ammonia. The heap quickly hits 70°c+ and requires turning every second day.
On the topic of yeast: it dies at temps over 55°c - otherwise will consume a lot of oxygen of it's left to autolyse (it'll eat itself before touching most of what's in your compost heap - I wouldn't rely on the yeast strains commonly found in the brewery to process anything but simple sugars). If you're cold-composting I'd heat treat the yeast before mixing it thoroughly through the heap.
