Where exactly might the free will be, then? Compatibilism is a fancy way of saying "free will so much does not exist that what determists call free will isn't

Where exactly might the free will be, then? Compatibilism is a fancy way of saying "free will so much does not exist that what determists call free will isn't even a valid definition to use as a starting point for investigating an answer." It's not an answer to the question, it's a denial of it. Another, simpler interpretation of Compatibilism is "if free will doesn't exist, then believing it exists or not has 0 effect on anything, because our beliefs are predetermined, and so at human scales the answers Yes and No are equivalent in all observable ways".