I don't think a path for deescalation exists anymore. JD Vance could maybe have taken the reigns by referring to Trump's ill health, promised to send more competent negotiators who could meet Iran in good faith, and essentially dropped Israel to save America (or at least give it a few more good years).
But that's a very tall order, and he just went out to claim Iran is designing nuclear suicide vests, so I guess he watched Wag the Dog and took some inspiration.