What is being done here is speculation. The Israel Commandos systematically destroyed all evidence. This was a criminal act by its action. It was a "dead man tells no tales" scenario.
The Mark Regev PR blitz is not to be trusted.

There is no real argument, here. A vessel bound for Gaza to break the blockade offering assistance for the Gazan people was attacked by armed military commandos with the purpose of throwing fear into the unarmed and peaceful resistance.

If you don't get that, then there is no discussion that will make sense here.