Siding with the minority here, in that I don't think the GM handled this poorly. And I posted supporting ideas in the original thread, hell, I was the one who archived it.
Firstly, the fight was horridly skewed against the OP from the start: one PC and a bunch of level 1 miners against a bunch of, presumably, high level druids and 4 more PC's. Even without any GM fiat, it was easy to see who'd win. The GM should maybe have given a chance to the supply run, but presumably the supply run went through druid territory. Druids are the types to use every animal, bird or tree out there as spies to find and eliminate threats. Those runners were doomed from the start. Suggesting the use of a fucking stupid rules loopholes like the peasant railgun was never going to do any good.
The GM should generally side with the majority in the group. Like I said, the odds were stacked against you to start with. If the GM had allowed you all the benefits you'd have needed, the rest of your group would be complaining about you being the GM's favourite. The rest of the group chose a side and stuck to it, just like you did. In a way, both sides were in the wrong, and in the end, like so much else, it came to bloodshed when it could easily have been avoided. You mentioned the others as being first-time roleplayers, so cut them a little slack at least.
So yeah, congratulations OP. You took a stand against impossible odds and got crushed. Sometimes that's what happens when you try and stand against the tide. Don't whine when the side you were on gets defeated, especially if you then try and claim that the others are bad role-players. You got beaten, adapt.
Like others have said, apparently have a change of heart, then make them regret it later. Never forget the tiny Village of What's-its-name.