I know that "nothing's impossible" but that doesn't sound likely. With an automatic, when you put it in "Park" it engages a park pawl (lever) into a cog in the direct drum inside the transmission. Pretty much locks the transmission from moving, if your torque convertor clutch was staying engaged you wouldn't be able to turn the engine over in park, realistically. Stranger things have happened but I would look more into something in the way of the tranny jumping out of park. Interesting problem though.
Take it to the dealer and explain what happened. If they bring out a straight jacket, run
Good luck.