Yeah the impurities thing is a good point, i'd be very careful,
especially when the stuff is not quite totally cured yet.
I almost got some standard silicone today too, but it was 5 bucks and
i was already getting a lot of other things at Home Depot this morning.
But that stuff might actually catch fire when wet, i dont know i never
tried this kind of test on silicone.
A one inch thickness might be too thick to measure the leakage
current with only 120v applied, so maybe when you do this make
a thinner piece too, like 1/16 inch thick or something like that.
I could try this too with the hot glue at least and we could compare
notes. I am guessing that it is pretty good, unless of course it
cracks, where moisture could get in and provide a shock path.
I've seen hot glue crack in several different applications when it
is bent too sharply or handled too harshly, so we'd have to be
careful about that too.
Happy testing
