Clearly Hawaii needs to get its act together...but it's also possible they're desperate enough to go for something non-traditional.
If they can bump up their incoming $$$ by an agreement with a power conference (and likely also more excitement), then it provides them a potential way out of the morass they're currently in
From the PAC perspective, sure it'd be great if Hawaii had a nice, big stadium... but the reason you're scheduling Hawaii isn't for their stadium or even for their football program. It's 100% based on the NCAA's Hawaii Rule. And that applies even if they're playing at a small stadium.