> Interestingly, 59 tonnes of gold was sold in USA and bought in London. So that means perhaps "Somebody" transferred 59 tonnes of their gold holdings to the USA.. who was that?

That 59T could have been someone that decided to starting owning gold for the very first time, so 'net-new' holding rather than a 'transfer'. The 59T could have also been multiple parties and not an individual "somebody": we only know that it was 59T from the sell side (NL).