The day after the "Grand Opening" of the new Tacoma Dome Station, where the WSDOT Secretary repeatedly stated "On time and under budget", I asked someone close to the project how it could be on-time, when I had heard the completion date change several times. I was told of this "year-end" deadline and the threat of having to return federal funds.
The day after the derailment, I asked a second person with good knowledge of the project and what I heard from the first person was confirmed. I kept that to myself, until I saw the Seattle Times article where this quote appeared:
"Sound Transit, the agency tasked with construction in some parts of that corridor project, wrote in documents in 2016 that the “project is under a very aggressive schedule” and that even a one-month delay would have impacts. It noted that the state was under a deadline with the federal government to be reimbursed for costs."
The entire article is linked here.
Perhaps, the year end date was wrong, but it seems clear to me that there was a dead-line to complete the project, that likely played a role, maybe minimally, in this tragedy.