Looking for help - Squash & Zucchini Looking Rough Lately (Pics)

The first image is a straight neck squash. Probably been in the ground (raised bed), for around 2 months. After the first month all was healthy. I harvested 3 or 4 squash from it and ever since it has quickly deteriorated in the last few weeks. In the second picture there are 2 zucchini plants pictured, not sure the variety right now, but you can see in that picture easier there is almost a white fungus / film on the leaves. This is my first time growing squash and didn't expect this at all. I haven't done any herbicide, fungicide, and/or insecticide treatments. Just been treating with miracle grow performance organics every 7-10 days. Both of the zucchini plants have 1 squash each growing well at the moment and seem healthy other than the leaves obviously. I haven't seen anything on the squash at all in about 2 weeks. Around that time I pruned and tossed 2 stunted squash that were browning. Just looking for some advice on where to go from here. I have a couple bell pepper plants and a couple creole tomatoes on the opposite end of the bed and so far they show no signs of this affecting them. Is there a treatment I can possibly recover with or is it time to dig them up? And if the latter what could I do in the future to prevent this. Thanks in advance for any advice!