This development will be located somewhat near the newly-accredited Bellevue College, which only recently gained 4-year degree approval. Perhaps BC will spin up their technology undergrad degree soon, then they might be able to feed undergrads into this new institute as well.
The vast majority of programmers, developers, architects, and IT that I've worked with in this area have degrees in other areas: business, sociology, English, sports therapy. It's become a tradition to major in an interesting subject during college, then leave that career behind for a better-paying job. And joining these self-taught software engineers are the ones who never attended college.
I wonder how this will impact the immigration and visa situation - I met some people in college who were not allowed to stay after graduation. The article implies that graduates will remain local and fill the glut of tech workers, but it sounds almost like Tsinghua University will be sending students there as well. So maybe it will be a program where Chinese students learn at this joint university, and then return to China?