They can order anyone who impedes them seized and handed over for judgement to the ICC, including bank CEOs and the like participating in retaliatory measures against them. They haven't done this, presumably for political reasons, but they can.
So if a US person has operated in the territory of a signatory, and committed something suspected to be a covered crime, and there is no US attempt to prosecute them, they can be prosecuted.
The US militarily can't intervene. They don't have the capacity to fight the Dutch, or French or the like, and the political cost of attacking other NATO countries is of course enormous-- it would be the end of the US as a superpower and lead to an actual EU-US war which would probably last for decades. There's a reason the US Servicemen Protection Act has an out, that it doesn't require any action. Think of it, not as a real policy, but as a dog making sure there's a fence between it and another dog before it starts barking.
Offences against the administration of justice
[...]
(c) Corruptly influencing a witness, obstructing or interfering with the attendance or testimony of a witness, retaliating against a witness for giving testimony or destroying, tampering with or interfering with the collection of evidence;
(d) Impeding, intimidating or corruptly influencing an official of the Court for the purpose of forcing or persuading the official not to perform, or to perform improperly, his or her duties;
(e) Retaliating against an official of the Court on account of duties performed by that or another official;"
So I'd say 70 (e) covers the sanctions imposed on those court officials. They are clearly officials of the court, and the sanctions are clearly part of retaliation against them. Consequently it stands to reason that anyone who participates in their enforcement or drafting or really in any way can in principle be prosecuted.
That's irrelevant and unrealistic in this case. None of this factored into the US reaching for the sanctions hammer with more and more despicable intentions, like supporting war crimes even of other countries.