Since the documents that Agent El gave to Nate.
Nate looked as if he was thinking hard as if his brain was being squeezed hard.
He tried to think about the possibility of what is meant by the Casino, whether it is a Casino with a real denotation or maybe only a mere connotation.
El has told even Nate that the VIP Casino card given to Nate is only useful for the Asian region, which is based at the Singapore Casino. In other words, the 'Bumerang' Casino is actually not only in the Asian region. It just has access requirements, which is different from the cards that Nate currently has if you want to visit casinos outside of Asia.
"I never thought that Anderson was someone who could be spelled out more mysterious than what I thought before," said Nate as he tapped his finger on his desk.
Because Nate feels responsible for what El finds, for that Nate tells El to return to complete his search.
