You really have a similar game to me ! I like how you tied the gun to the car direction. Also you have AI for the opponents, that's a crazy feat to have for a gamejam, my zombie are, well, brainless :D
I deliberatly hid this information to the player so they start to ask themselves "Why am I in this eternal loop again ?" and try other things. There's also a super secret ending : spoiler spoiler spoiler where you can destroy a factory but they have a lot of health so it's long and I'm guessing nobody tried that