No, but I have been to a cocktail party in a British submarine. If that helps.
Only the poor man’s version … place a mic inside a carboy (big plastic water bottle for water dispensers) and put it under water. Probably numerous other containers could work, but something transparent sounding and large enough for the mic to suspend in the middle of the container. You have to hold it in place and can’t get too deep because of displacement. I guess you could put some water or weights in the bottom of the carboy to help it sink, but make sure the mic doesn’t take a dip.
Maybe you’ve heard the story Beatles engineer Geoff Emerick related in his book “Here, There and Everywhere” about underwater mics?
Apparently on the tune “Yellow Submarine” John wanted an underwater sound for his voice so the lads debated how to submerge Johnny and the mic without encountering the deadly 240V the Brits use in their systems. Someone suggested just using a condom for protection (it was a sixties thing, they all had them in their wallets)
The book is a great read, and there is a summary of the story here: