This two star hit the nail. Putin’s army is not the Red Army of Brezhnev that could have rolled over NATO in the 70s. It may be well equipped but it’s not large and not really capable of large scale sustained offensive ops.
Logic would say that neither Russia nor the Ukraine would want to sabotage the pipeline. So it comes down to one of these two: pro-Russian militias in the area, hoping to get more support from the Russian military across the border, or the US if you believe that any parts of the US administration want this war to start.
I would say it’s more likely to be the pro-Russian militias, hoping the war would start and they could accomplish more of their goals with more support from Putin’s forces.
Putin would probably realize this and not change his plans just because of this incident. Whatever those plans are, he won’t be drawn in by a third party.
A “well-armed gas station”?