Thanks for your kind words. I think the flames coming from the vents ignited surrounding stuff. Higher up there was mostly radiation and there the damage is not that bad although it has burned there and also underneath the dash.
Regarding the hose connection, in my view it can add value in two stages:
1) At the very beginning of a fire where you might be able to cool it down to stop thermal runaway
2) At the end of a fire to ensure it does not light up again
Then just a metal (quick connect) cap can do the trick.
At the hottest point during the fire I'd not suggest to use/open it.
In my box, three Tesla modules burned until there was nothing to burn anymore.
When the heat was more or less gone, the firefighters tried to open it, but I suggested to cut off the MSD instead so that was the way to extra cool down instead of the hose connection. See photo 2 here
But in your case (if you still want Tesla modules on a boat) I'd say try to ensure each module is contained so in worst case it can burn without igniting others.
Think the issue in a Tesla (and others) and the main reason for submersing cars is that you never know if the surrounding batteries got just too hot or not.
In my case I was quite sure the front would not re-ignite since there was simply nothing left to burn.