Iran WANTS the deal, Russia wants the deal, China, France, Germany, UK, and the EU all want the deal!
Why would they all abandon the deal......?
Now there are a couple of options.
One would be to do nothing, let Trump impose sanctions.
If Trump imposes tough sanctions against companies doing business with Iran, then the deal will probably fall apart...BUT THEY DON'T WANT THAT!
Another option would be for those countries to renegotiate a tighter deal with Iran in an effort to keep Trump from reimposing sanctions.
The ball is in Iran's court now, cave into a better deal and keep trading with the rest of the world, or go back to pre-deal sanctions by countries preferring trade with the US vs Iran!