I think the whole notion of a facility-specific rapid-response mechanism simply hadn't been developed in that kind of detail at that point. To have disciplines targeting specific facilities in another country has never been done before. It did require a much longer negotiation with Mexico in particular, because they are the clear target of this. Working out all of those details was contentious and took a long time. It simply wasn't addressed in the first instance.
On February 24th, 2020. See this statement in context.