I think that's Haye's best bet. I'd think +300 sounds about fair for Haye. UD is a remote chance should Haye knock down Wlad more often than Wlad knocks him down over 12 rounds. Quite unlikely. Rewatch Wlad - Brewster I to see the amount of terrible bombs Wlad landed on Brewster before he was stopped himself.
All jokes aside, don't let the Haye hype take your money. Haye has almost no chance in this fight. Hold your money for somthing better than this...