That can't be right. First, your Delta study is woefully lacking in school - specific information. Second, the college confidential link's methodology seems to be missing a lot to me, particularly in the way of revenue. For example, for many universities (eg UPenn) the parking department is actually a huge revenue driver that must be taken into account to calculate overall university P&L, and that kind of thing is completely ignored here. Schools are businesses; you can't just ignore the other sources of revenue. As such, those estimates are hugely over inflated. Is Yale really spending $100k PER STUDENT each year? How could that possibly be?
Let's look at Stanford. Wolfram Alpha claims 6532 undergrads, $37380 tuition per year. If student cost was truly double tuition, Stanford would be operating at a loss of $244.4MM per year, and (all other considerations aside) the $12.6BB endowment would be gone in 50 years.
Ultimately, the reported cost is often based on some key assumptions that aren't always stated, and I'm pretty sure we as a population don't actually have much clarity on the true cost of educating a student, if it's even possible to really quantify such a thing (try measuring the monetary cost of creating a supportive environment or a caring teacher).