My first outdoor grow photo period GDP

Another hot week down. For the most part, we have gotten A LOT of rain this summer. I’ve had issues with certain plants in my garden dying for absolutely no reason. I pulled a squash plant that was wilted and the base of it was mush (last picture I uploaded), and full of grubs. The squash plant was right next to my two GDP’s. I checked the other squash plants and found that 80% of them were full of these grubs. I’ve never had a garden, and I’ve never had a serious grow before, so obviously I’m panicking. I have insect/grub killer for my lawn that I never used, and spread some of that throughout the garden and around the twins, and immediately turned the sprinkler on and left it for a few hours. I’m hoping and praying it’s not too late, all my weed plants look happy and healthy still, but I still intend on getting something better, and more geared towards getting rid of grubs around gardens. What do you think?