Nearly 400 defects were identified in the first lot of baggage cars
Don't get hung up on the number of defects. We deliver warships with thousands of trial cards written, some covering multiple occurrences of the same defect. These things get fixed, which is why they spend time between delivery and revenue service.
so like Nippon Sharyo they may not be able to meet USA specs to one degree or another.
If they didn't meet specs, none would have been delivered. The fact that there are cars in revenue service (and have been for quite some time) indicates that you're mistaken.
I could certainly be wrong about CAF walking away from the rest of the order
You are.
but when they are shipping dollars with each unit it doesn't make good business sense for them to deliver.
Objection: Assumes facts not in evidence.
It makes perfectly good business sense to keep delaying deliveries ( which they are doing) until Amtrak gets fed up and cancels the order which is probably what CAF is hoping will happen. Am I wrong with the facts or with this analogy? If so please explain how.
As usual, you take some wildly wrong "facts", then use them to jump to a logically unsupportable conclusion. Bonus points for consistency, though.