I mean, speaking on the assumption that it would have only taken a few punches to end the fight then yeah David Haye definitely could have won that fight.
He kept giving up too much ground too quickly. His feints and weaves were working, triggering Wlad's tendency to step back and so instead of edging forward, Haye would carry on retreating and undo a crucial part of the process, which was to get Wlad to panic punch.

I think the miscalculation in Wlad's speed upset Haye, cause obviously he thought he was the superior athlete... That and the sheer difference in physicality (was not prepared to be leaned on at all!)