deSitter
I would then propose an alternate theory - from the visible damage to the tail section's lower region - the presence of middle and rear mounting boxes that have been torn from the empennage structure - perhaps the front mounting lug failed, (then bad things happen)
Sure, if the front mounting lugs weren't doing their job bad things would likely happen. The question isn't so much how the tail would subsequently unravel in your scenario, but why the front mounting lug would fail in the first place.
You can't say the tail would or wouldn't have fluids on it, especially after being in the waves for a few days. An estimation of 'likely or not' doesn't matter either.