Koons is the prototypical example of delegation (to carefully selected artisans), but many less notable contemporary artists delegate realisation to fabricators (I have seen this first hand only in sculpture.) I think the fact that this is now acceptable has something to do with the decoupling of visual art-as-concept from art-as-object that has occurred over the past 150 years. The rise of CAD also makes it easier to design a work and delegate fabrication. Of course Music and Theatre have been delegating realisation pretty-much forever.
Money laundering itself in the art market is duller, by design, it trades on lesser regulation and inspection of the funds bought to sales and auctions and often uses decoupling mechanisms, illegal funds -> art -> inflated values -> legitimate money via loans backed by art as collateral, etc.
Searching a bit I found two articles that seem okay on quick skim reading:
* https://alessa.com/blog/art-money-laundering-explained/
* https://www.dentons.com/en/insights/articles/2024/march/11/t...
https://en.wikipedia.org/wiki/Made_You_Look:_A_True_Story_Ab...
https://en.wikipedia.org/wiki/Exit_Through_the_Gift_Shop
Freeport facilities are part and parcel to enabling these complex businesses arrangements, and they are mentioned in an aside in the documentary Made You Look; the Geneva Freeport being one of, of not the, world’s oldest and most important such facility is called out specifically if I remember correctly, or maybe one in Antwerp.