If Clark Lea is absolutely 100% dead set on leaving to be a head coach and build a program, then there is nothing Notre Dame can do.
Assuming that's not the case, this will be a pretty big litmus test for the university. Being great at football is a very good thing for the university, and Swarbrick and the administration are smart enough to know that Notre Dame simply cannot go toe-to-toe with Alabama, Clemson, Ohio State, USC, Georgia, etc on a number of fronts. We cannot recruit like they do, look the other way as egregiously as they do, etc. Basically, Notre Dame cannot run a semi-pro operation.
Basically if Swarbick and Jenkins can't figure out that much of the reason Notre Dame competes with elite programs is to have elite coaching, then that's a pretty dismal sign for the program. I mean at that point you're just resigning yourself to never be a top 4 program.
What's another million or so when they make it back in droves by being an elite program? Pay the man.