John's care sheet is awesome and has helped me so much!Yes, tank quality turned out to be an issue when I tried that with the toads. I was amazed at amount of poop those guys put out! And it doesn't stop after metamorphosis either
How big is the tank that they're in now? You can try to make a "beach" area, like a stack of slate rock, and/or place some sticks in the water so they can climb out, but you still run the risk of drowning. It'll also decrease the water volume in the tank. I did do that for the first 3 that morphed, and didn't run into problems except for constant worrying.
Oops, forgot that you mentioned you had containers on hand. Okay, would said neighbor be willing to do partial water changes if you left a couple jugs of dechlorinated water on hand? Then there'd be no scooping involved...and they are hard to catch, hehe. And the water wouldn't be so yucky. On the plus side, they seem to stop eating after the front legs come, so less poop.
Did you find a way to cool them down?