Hello,
Sorry to hear that.
Sadly, the use of pesticides WILL have a bad ending for everything that is currently 'living' in the garden
You could try putting the frog in a container of clean water ( with its head above the water) and let it soak / keep changing the water every 10- 15 min minutes for a few hours ,then let the frog loose.
It may die, anyway. I'm sure you will feel better that you tried.