I tried some wasp nest years ago in my CVA Mountain Rifle in .50 caliber.
I didn't note any burning "paper" flying out of my barrel. I managed to find one wad on the ground, after firing, and it was intact.
A few years later I read a gun writer -- can't recall who or where -- who had the same experience: the nest material didn't burn and was found on the ground, relatively intact.
My one experience echoes his.
But nothing is absolute, so I won't go down as saying that wasp nest doesn't burn after leaving the barrel.
I don't know that I'd use it in cap and ball revolvers. I don't expect it would cause any harm, but I don't see the point or advantage, considering that greased felt wads are easier to obtain and use.
But who knows? The gods are perverse. It may be that wasp nest in a cap and ball revolver is absolutely the finest accessory you can add when loading.
The more I delve into black powder, the more I realize how dad-blamed complicated and persnickety it can be. Its use is hardly as simple as I once believed.
Wasp nest in my cap and ball sixguns? Hmmmmm ... I have none but I'll have to keep an eye out for it. Might be fun to experiment with down the line.
If you try it in your cap and ball, let us know how it goes.
As for sealing off the chamber from multiple ignition, I don't know. But then, I'm not one of those who believes that multi-ignitions start at the front of the chamber. I believe it starts at the rear, when flame gets under the cap, or through the uncapped nipple, to ignite the charge.
I just don't see how flame can get past a ball tight in the chamber, provided the chamber is round and the ball is large enough to create a good seal.