It would be interesting if one could get hold of the Watchtower's inhouse Financial Statements, as this would indicate whether the Society is involved in money laundering or not. After all, who are their vendors and what are their actual expenses?
The Watchtower can make large cash deposits without raising suspicion, due to what they claim to take in from their conventions. Moreover, there isn't any law that says the Watchtower can't pay twice or three times the market rate for goods and services. Since the Watchtowers Accounts Payable journal is not open for public audit, there is no way for us to know if it contains suspicious payments to companies linked to organized crime.
Again, I'm not saying that the Watchtower launders money for outside interests, still the opportunity is there.