The wallet server has all the xpubs for non dojo users & the xpubs with a bunch of 1m, 5m, etc sat UTXOs in their histories are the postmix accounts. *If* the feds have the wallet server, they can find the postmix account, find the corresponding other three accounts, and cluster every users transactions & mixes together, so unless a user never touched KYC, their name would likely be tied to their cluster.

Don't forget, the guy who wrote those posts...is now in prison. Whether prison for this is right or wrong (it's the latter), the samourai guys clearly didn't have it all figured out.