I'd have to lean toward Genis, due to Surfer's pacifist nature. He wasn't able to handle insane Thor very well, when he clearly had the capability to do so, but just couldn't bring himself down to that level. Same scenario would probably unfold here. Surfer would recognizse Genis as an ally and try to reason with him...and get his ass whipped in the process.
Insane Surfer would show Genis the true meaning of power...and quickly, too.
Oh yes the universal reset that brought back the Kree, right? I didn't actually read that story, but heard about it. Did he actually do it under his own power?
The kree were already around. No Eternity's son Entropy came to Genis for help killing Eternity, and they went and did it, ending the multiverse (off panel, but later we see Genis crushing Eternity in his hand). Then Genis shot Entropy in the head, which released Entropy's power and turned him into the new Eternity.