At least he got to feel him for a minute before he got off. I've never caught a fish on the frogs or rats. But I've had them come up like that and or knock the frog several feet into the air and never get it in their mouth. I use to fish a pond that would be covered in milfoil mats and that's all you could really use there was frogs/rats or weightless soft plastics and let them sink into the little holes. It was always fun to have them strike from under the thick mats though.
The only thing I ever caught on on a rat was...let me tell the story. Was fishing my cousins pond that is covered in green duckweed. Was working the rat across the duckweed and actually saw the ripples and wake in the water as something was coming for it FAST. BOOM the water explodes and I stick whatever it is and start fighting. Hmmm something don't feel right...and in comes a daggum snapping turtle with my rat in its mouth. I let it keep the rat!