They have to win in order for the extra wound boost to be in effect. I'm not certain if that situation is explicitly addressed, but since you only inflict wounds if you win, I think it's a logical conclusion.
Warhammer 40,000 Campaign Skirmish Game: Warpstrike
My Spelljammer stuff (including an orbit tracker), 2E AD&D spreadsheet, and Vault of the Drow maps are available in my Dropbox. Feel free to use or not use it as you see fit!
Thri-Kreen Ranger/Psionicist by me, based off of Rich's A Monster for Every Season