Azzrik757,798 Locked 26 May 2014 02 Jul 2014
Hooray, as of the release of the Tactical Taco DLC the previous bug has been fixed.
All you have to do is win 25 matches of Gardens & Graveyard, any way shape or form, and perfect wins now count. You're still able to switch to the winning side just before the game ends and it'll count towards your total.
*After the Zomboss Down DLC was introduced a bug was also introduced that perfect wins would not count towards the Garden Tour achievement. The Zombie Perfect Win was also added during the Zomboss Down DLC and unfortunately in order for Zombies to win, they'd always fulfill the condition of a "Perfect Win" which oddly enough did not count towards the achievement. This has since been fixed.