It's a fun little endless shooter!
But a few things I'd like to mention are:
It's Very easy to leash zombies. I practically didn't feel threatened by the zombies at all during my play session. That's why I think more variants for the Zombies (like sprinters, tanks, some projectile shooting enemy etc.) that add challenge would be great. I was also able to stand still and let my companions and turrets do the shooting from wave 9 on out, so the enemy scaling should be much steeper.
Smth seems to be set up weirdly with the project, because the game kept starting SteamVR and my VR headset. You should check your Unreal settings and see if there's a checkbox controlling that!
Aside from that, I think Lucis mentioned a good few points and still want to congratulate you on a successful submission!