Exchange -> Address A -> Address B -> Mixer -> Address C
It's difficult for anyone to say for sure, but as I said in my above comment, if an exchange will block your account if you mix your coins immediately after withdrawal, then I can't imagine that a single extra hop is going to make any difference to that, especially if you are moving all the coins in one without any change.
What I want to say is following: Let's imagine I have dynamic addresses (all of them). Received money from an exchange to wallet A, then sent from wallet A to wallet B, from wallet b - to mixer. From mixer I sent it to my main wallet but what I do is that I split chips and sometimes send 0.3 btc, sometimes 0.7 btc. I collect bitcoins and send different stakes in order to get rid of any suspicion.
I received money on A and sent to B. I'll claim that wallet A is my primary address and I have an unpaid loan of a person that uses wallet B and it's not my job what he does with walelt B.
Also, another reason why that rule is dumb is that what if I want to send btc to my friend and he sends me mixer address? Is it my fault? How should I know whether address belongs mixer or not? Dumb rule!
Anti-money laundering politics is the worst politics ever, worse by the logic behind it. Rich people launder without any resistance It's very hilarious, it's a joke.