Finally, yes, a rocketing gas tank would need to accelerate for a few metres to knock a hole in a seam, but that folded-up bit of fuselage is interesting nevertheless.
If we are to believe the report of the first 'clunk' (20 mins ex-LHR), is it not possible that was the alleged bottle dislodging ? After which it could have rolled around down there sustaining increasing damage until it finally let go from an undetermined position; conceivably the necessary 'several metres' from impacting the skin.
Speculation. So sue me.