Believe it or not, companies are legally required to do due diligence on such things. For example, I work for a huge bank and when there's even the faintest hint of money possibly being funneled through an intermediary to a sanctioned state/person or a company on the Entities List they will absolutely send someone to investigate. Physically, if it is deemed necessary.

A multi-billion dollar deal in Singapore would absolutely require some folks to physically go out there and do some inventory at the very least. It needs to be in the realm of, "We walked the data center and counted how many of our products were installed and we were shown their yet-installed inventory" documentation. "It matches what we sold them." A great big, fancy report. With pictures.

How much would that cost? Basically nothing compared to how much trouble they could get in for not doing that due diligence. Compare how much it would've cost against how much their stock just dropped.