Bakugo uses Cluster constantly as a part of his fighting style. He's gonna be blitzing Dabi from the get go especially since he could
blitz complete Shiggy with it. Dabi is faster than Endeavor, sure, but Endeavor was being overwhelmed by Incomplete Shiggy in terms of speed, so that's really not good for Dabi
It doesn't matter if Bakugo knows if Dabi has Endeavor's moves or not, all of those moves can be dodged with Flight + colossal speed advantages.
Dabi is also not actually stronger. Dabi might be superior to Endeavor and Shoto, who can harm All For One with their heat, but Bakugo being able to burn Complete Shiggy with Cluster, harm him with Cluster, and potentially kill him with Howitzer Impact: Cluster means that Bakugo actually scales very close to if not higher than Dabi.
There's also no reason to assume Bakugo wouldn't use Howitzer Impact: Cluster before Dabi explodes anyways, seeing how he has intel from his friends and others about how dangerous and unhinged Dabi is. If none of his other attacks work on him, he has no reason to not Howitzer his ass to kingdom come.
The only thing Dabi has going for him is his Suicide Explosion, but that's only assuming he uses Phosphor off the bat and starts unga bunga storing energy, which doens't really make much sense as Phosphor was used as a last ditch effort to not get frozen by Shoto, which Bakugo can't do here.
Claiming that Dabi would use Phosphor as an amp also makes no sense. I have no idea why Phosphor is treated as a stats amp in the first place, seeing how it's not treated as one for Shoto, and Dabi with Phosphor and going completely batshit crazy was still unable to kill Endeavor even with several bloodlusted attacks.
TLDR unless Dabi uses Phosphor and kills himself, he's not winning. Considering it's far more in character for Bakugo to use Howitzer than it is for Dabi to use Phosphor, Bakugo wins.
Voting Bakugo