All of your plants are chlorotic, in this case it appears to be a severe lack of nitrogen but it could be a lack of micronutrients. Have you fertilized, with what and when. Yes, they can be saved.
That is the reason. Coffee grounds have about 2% nitrogen and very little if any phosphorus or potash. This nutrition problem is only compounded when growing in a container as the nutrients quickly leach away when watering, so any nutrients that were in the soil when you planted is now gone. With heavy feeders such as squash you should fertilize every time you water or at least every 2 weeks. Get some good organic liquid fertilizer and start fertilizing. Also get some Chelated Iron and use per directions.
