I sprayed my two foot tall heirloom tomato patch yesterday with Serenade fungicidal, but mixed it too strong at 6 oz/gal. The result is seriously wilted plants for past 30 hours. Rinsed them when after 3 hours they exhibited wilt, but they haven't bounced back yet. The leaves and stems seem to still be succulent and not "crispy" and they haven't "died," only fairly severely wilted. Ever heard the results of someone being so careless? 120 total plants...
Fungicide Spray on Tomatoes
Certified GKH Gardening Expert
This is likely an oily coating and rinsing the plant is futile.
You can provide some shading to the plants to try to reduce stress from the sunlight for a few days.
Unfortunately you are in the wait and see period of gardening.
And you are not alone, this sort of thing happens!