Putting my tin foil hat on, let's assume that someone made counterfeit pagers with the explosives inside it, probably attached welded to the circuit board or battery, then slapped a company label on it.
So either the Taiwan and Japan companies made those weaponized devices, or they are the pasty in this case.
We do not need a tin foil hat to realize that why would a company prefer to be known and associated with selling exploding devices?
Uh, no. That makes no sense at all.
So either the shipment was intercepted then tampered with, or someone made counterfeit devices.
If the boss gave the order to do this, then what does that CIA person do? Probably better to do the latter option.
Then, it could be like the movies, where they know there is this shipment coming from the pasty company, then at the port, the customs official makes the switcheroo.