I actually don't mind this theory. However, if you're going to do it, do it at Payback - The Allstate Arena, Chicago. Bo Dallas instantly gets all of the heel heat that he could want, by costing a heel a match against a babyface. It could be a really, truly interesting dynamic.
It's probably an unrealistic proposition because ultimately, a feud between Bray Wyatt and John Cena deserves a better ending than that but it's interesting to contemplate how the new way that babyfaces and heels are thought of could be further used and warped in the future.
That wouldn't be the end of the feud. If I were to book this in more detail:
ER: Bo costs Wyatt the match, Cena doesn't know.
Raw Cena tells Bo what he did was wrong. Bo says he wants to be like Cena.
The build to Payback is a 2 on 3 handicap match: Wyatts vs Bo/Cena. You build it so you (and Cena) aren't sure if Bo is genuinely wanting to be a hero like Cena or if he is a Wyatt mole.
Payback: Bo fights his heart out against the Wyatts. Cena almost has it won but Bo costs Cena the match.
Raw, Cena and Bo argue. Bo cries. Cena feels bad.
Raw 2: Cena wins a qualifying match with Bo in his corner. Cena acting kind of like the big brother having to take the little brother with him. Regretfully allowing him to tag along. Bray is cutting promos about how it hurts him to see Bo looking up to Cena.
MITB: Bo accidently costs Cena the MITB. Cena snaps and beats the shit out of Bo.
Raw, Wyatts "call Bo back to family" since he was the one who showed the world how ugly Cena can be.
The build for Summerslam is that Bray is proud of Bo, but Bo still things Cena is a hero. Cena is struggling with his actions.
Summerslam is Cena vs Bray "I Quit" match. Finish is Bray handcuffs Cena to the ropes then threatens doing something awful to Bo, iunno, chair shot/stairs shot combo. Cena says "I quit" to save Bo. Then Bo stands up, hugs Bray, then all 4 Wyatts beat the Cena beyond belief.
Just me, I'm sure there are holes in that and ways to make it better, but that's the gist. Either way, I'm very excited for this.