... Which is why ChipMixer will not refund.
Good explanation, this makes perfect sense to me.
So i'm wondering as well - what if someone decides to frame Chipmixer by saying that they got hacked/chipmixer did an inside job when they really just sent the bitcoins to themselves? there would be no proof either way, but the guy can do this under multiple accounts and then people will say chipmixer is a scam.
There is nothing any site can do against this. You can say any exchange, casino or other site gave you a deposit-address and changed it right after you deposited. The site can't prove it isn't true, while you could screenshot or even record the whole action with a simple "inspect element > change address" in your browser.
You can only be sure a site has no interest in doing so, as it earns more in the long run being honest.