How is "Because the NSO group handles dollars" related to "the court could order any assets the US can get their hands on seized"? Presumably, if they were getting paid in bars of gold, the US could seize those too, if they could get their hands on them, no?
On the other hand, if they were paid in US dollars, but in cash, that wouldn't establish jurisdiction, nor could it be seized, if the transfer happened outside US territory?
On the other hand, if they were paid in US dollars, but in cash, that wouldn't establish jurisdiction, nor could it be seized, if the transfer happened outside US territory?