John Chen was an idiot
He signs a secret deal with Barlett in California, then arrives back in Hong Kong on Bartlett's plane, arousing questions. So many plot points derive from this, which bothers me because it's such an obvious blunder.
shareHe probably was going to try to suggest he helped set up the original non secret deal - nothing suspicious about that.
He did get sent to America, I assume his father and the Tai Pan figured he'd make contacts, find possible business opportunities.