1. Hold an emergency team meeting and tell the team that everyone needs to step up, including the coaches.
2. Give Tuiaki an ultimatum that if the defense caves against Boise State, he will be gone.
3. Give Grimes an ultimatum that if the offense doesn't pick up and start showing significant progress over the next few games, he will be gone. (Grimes deserves a longer leash than Tuiaki because this is just his 2nd year, as opposed to 4 years for Tuiaki).
4. If Tuiaki leaves, ask Ed Lamb to be the interim DC until the end of the season. Go out and hire either Justin Ena or Kelly Poppinga as the new DC. Raise money from big donors to make it worth their while.
5. If Grimes leaves, hire Paul Peterson as the new OC.
I would give Kalani one more year, and if he doesn't get to 8 wins, hire a new head coach.