I lowered my water depth a few inches and I have taped up any gaps in the lid.. unfortunately I am still using a HOB Whisper 40i (which caused the 1/2 inch gap my frog managed to escape through!) until my new Eheim 2217 accumulates enough 'beneficial bacteria'.
I have no openings now so I am pretty confident now there's no chance of escape, they certainly do seem to work hard at escaping!
Almost makes me wish I had a 3/4 water and 1/4 land set up to see these guys outside of the water now and then..