According to some next day reports, Corbett was winning the second fight He didn't take the first fight seriously enough, opting to fight up close when it was clearly not the best way to deal with it. Considering Ruhlin learned from Corbett, was almost certainly inferior based on their fights with Fitz, and Jeffries, and beat Sharkey twice, I think it's safe to say Corbett could have beaten Sharkey
According to what I've read Corbett's second Con McVey jumped into the ring to save Corbett from a ko. I'm sorry I don't understand the underlined.
By all accounts, even ones that were said Sharkey was doing better, Corbett was doing better when McVey jumped in than earlier in the fight. So the claim McVey jumped in to help Corbett is likely completely false.