DEADCRAFT - It Came From the Junkyard

I forgot i purchased the deluxe edition THANK YOU!!!

I was looking forward to playing this after beating the main game until, I reached the point in the story with a gate defense mission. I could not figure out how to stop the horde from taking down the very flimsy gate. They move so fast and get through defenses before they fully engage. If it had a single easy strategy i missed it or lacked the resources . What makes it worse is starting the scenario locks the junkyard off from access due to it engaging gate defense as you approach the area.