Asset valuation and cashflow are not the same thing. There are ways to make an asset (in this case, Everton) worth more while causing it to generate less cash day-to-day.
Suppose that you take a piece of otherwise worthless land and invest to redevelop it. You borrow to do this. This causes the underlying land to become worth more, but costs you the price of servicing the debt. The value of the asset goes up, because the stadium is basically worth what you pay for it and the land value increase is more or less free since the dirt costs you nothing, but you're paying interest and generating less day-to-day cash to accomplish that.
Now suppose that the local government, in addition to giving you the worthless dirt to redevelop, hooks your asset up to a transit system. You get the spillover effects from this for free since the transit system is on the government's nickel, further increasing the value of your asset.
The net effect is that you have less to spend on players annually, because you're paying more in interest than you're getting back in new revenues from the project. (If you don't believe me, run the numbers on gate receipts from an increase in capacity yourself, and compare to the likely interest costs. Remember that you don't start getting the gate receipts until the project is done, but start paying interest right away.) However, you pocket both the increase in the value of the dirt and the transit system spillover effects when you sell the asset.
As long as the asset price increase is greater than the difference between your total interest costs and the total bump in gate receipts by the time you sell, you come out ahead on the deal.
If you screw this up really badly in terms of cost overruns, you bankrupt the club. That's a risk rather than a certainty, and Dave's not communicating that very well. A more realistic interpretation is that Moshiri comes out ahead and the fans lose until the debt is fully serviced, at which time the club's finances are probably better off than they were before. But you're probably looking at a decade on that, and we're not going to live forever.