I got good news tho, please read the section at the bottom of the original post.
How sure are you?
I am not convinced that any of the characteristics you have listed are enough to make a definitive link between these two accounts. It seems to me that there is a not insignificant chance that you have just stolen $500 worth of bitcoin from an innocent third party.
My thoughts exactly. Even though it sounds likely, is (for instance) 80% really enough for this?
There's much more than that going on in this case. Say for example, how high are the chances that someone will pay a 5% fee for a crypto <-> crypto exchange when they can use KuCoin to do that for a much lower fee?
I guess it depends on how often you do these trades. If you do it several times per day, it could be a coincidence. If you rarely do it, they're likely the same.
Even instant exchangers can do such a trade at 0.5 to 1% fee.
I am still verifying the transactions tho and I am going somewhere with it, like the scammers address being connected with the second persons address.
Try
https://blockpath.com/