Its possible the customer caused issues. But right now there simply isn't any indication of that at all. They never even got to the stage of having a mockup that could have generated change orders and the inevitable production delays.
This is an insightful comment, which leads me to ask: Given that this procurement was with public money for a quasi-public agency, why on earth were we kept in the dark? It seems to be about as secret as the Manhattan Project. I think the riding public and the politicians who wrote the check deserve a better answer than "you might see some siemens cars show up in a few years".
Further, I don't mean to channel our polarizing US President, but shouldn't someone on the railroad or agency side get the toss for this? There's someone in charge of procurement, and their job is to successfully obtain rolling stock that can then be used for the core of the business - moving passengers - because the old rolling stock is at the end of design life. If you can't manage that process, you get the ax. I spend a lot of time going between engineers and purchasing agents. They don't just wait for the load test (similar to the crush test in our biz) to find out the equipment doesn't work as designed. They have checks at every stage of the process and they also don't order wild-ass custom* garbage because it leads to delays. The purchasing agents and project managers on the customer side know that if they can't manage a project to completion and on-time, they're not worth employing.
*That is, unless it's government work. Then they buy the most wild-ass custom stuff you can imagine. I'm about to no-bid a project for the DOE because it's got "lose money" written all over it. But some sucker will take it and they'll fight all year long.