I just got one of the female Zs I have for the game, and she seems to be almost exactly 21 mm from footsole to eye.
I'd say yes, a fairly good match. I also think I've seen them used with 20 mm / 1/72 minis before.
You can buy the figures separately, too (Bag'o'Zombies), and you can even get some that glow in the dark
