If that were the true intent of the law, it could simply say "whenever the President chooses," instead of detailing precisely what the president must, "find as fact." Even the administration believes this, as they chose the particular fig leaf of "reciprocity" to defend that the statue was being followed.
Legally, there is a major distinction between whether an entity charged with making a finding as indeed done so, and whether that finding correctly reflects the actual facts.
This is not a novel concept. When courts review laws made by Congress, they don’t get to second guess Congress’s economic reasoning. Congress could ban interstate transportation of beer on Tuesdays. As long as the law was within Congress’s commerce power, courts don’t get to second guess the rationale for the law.
But that's not the argument they're making. You are discussing whether Congress is allowed to pass such a law (they are), GP is discussing the gap between the statute and the executive's action -- that absolutely is reviewable.
In particular, Section 338 requires a factual finding (from POTUS, which is not directly reviewable) but then also tasks USICT with "ascertaining" the facts. It doesn't explicitly give USICT ability to review the factual finding, but it's a very plausible argument that if USICT is tasked with ascertaining facts and those conflict with POTUS's declaration, then POTUS is exceeding statutory authority.
338 has never been used and it's not clear it'd pass Constitutional muster to begin with.
