Sounds way more complicated than just using an ATM though.You can buy crypto or physical metals. Then (theoretically speaking) you can find people wanting to get rid of their cash for crypto or physical gold off the record.
Practically it's rather difficult to find a counter party you can trust and that trusts you at the same time (matter of physical safety), clean money (depends whether you care of course) and a safe place reachable for both of you. huh...
Western Union is really a private company but Governments in some countries do keep an eye on the movement of money in and out of their countries and Western Union is exact one of them, however, you asked for a solution and yes it can work provide you do not abuse it. Let say you open a dozen accounts and send money to them remotely even Western Union. Final you go and collect them from each in bits and pieces and in a short time you should be in position of a hefty sums of cash.Western Union is overseen by government, is it not? How can it not be, since official government institutions (postal offices) offer this service.
About 30k$.Concerning western union, there is a limit approx 7500 euros or USD depending of the jurisdiction. When you reach this limit, there is an exchange of information. I can check more if it s really important.
There is several methods to cash out but the question is : About how much money do we speak?