AML works against the small time criminals but when the sums get large they have access to much larger infrastructure and good old creative accounting. By infrastructure, I mean states.
That said, every once in a while a larger fish is caught. Right now a huge topic in Turkey is about a local businessman laundering about $1B of a US Mormon sect that stole the money from the US by faking business activity and receiving subsidies.
In this case, the Americans are in prison and the Turkish guy is in Austria, awaiting extradition.
Shortly before things got sour, the guy had access to the highest Turkish officials and was the darling of the media.
On the US side of the things, apparently the criminals were partnering with a high ranking CIA official to pull this off.
Here is a video on the topic: https://youtu.be/BPZIX5oBrUc
It’s already out of date as more money and connections were revealed since then but if you Google the names, more juicy stuff comes out. Sezgin Baran Korkmaz is the name of the Turkish guy allegedly laundered their money, now under arrest in Austria. Erdogan scrambled to remove his photos with the guy from the internet.
It has been revealed that they bought old Turkish companies that were under financial troubles and used these to move the money.
Why Turkey? Because Turkey is in economic turmoil and to motivate people bring money in the country they passed a law so the state doesn’t ask the origin of the money and politicians facilitate the bureaucratic process(allegedly for a substantial commission).
Pretty straightforward laundromat.
Once the money is in the Turkish system, they have access to EU, USA and pretty much everywhere because according to the paperwork the money is coming from legit companies, some a century old.
I bet you, Turkey is not the only rough agent here.