This just about sums it up.

"Please... assume the position."

Please, assume the position.

Nothing is canon until confirmed- him existing in another game would make him being alive canon.

Originally purposed as and reprogrammed for are different things, though. I doubt anyone from before the war is around to make sure they are doing their original tasks. The Gun Runners weren't selling guns pre war, but they have a robot that was programmed just for their needs. Even knows how to answer questions asked about the Gun Runners.

As for the color. Could, be. But could it be sun bleached, instead?
When I saw him walking outside the first time, that is where my head went. Sun bleaches and discolored. A bit of rust to boot.
Most of the pre-existing "creatures" are reworked for this game, with much more detail. The whole world is this time around. I dig it.



Any rate, I think all this said is that some protectrons are different colors.
Construction or more accurately, Heavy Industry bots being yellow makes sense.