Would it be a huge shock to find out some conglomerate like Koch Industries or ExxonMobil were involved in an astroturf campaign
Maybe not, but there's no evidence of that here, it's pure speculation.
The influence campaign being perpetrated here looks very similar to Russian operations against former Soviet states, where they encourage or create a "separatist" movement within the target nation and then antagonize both sides until the separatists eventually break off a chunk of territory from the target nation, and then wouldn't you know it Russian troops show up and "help" establish a new orderly, Russia-aligned government. For example:
"... the South Ossetia war and the Abkhazia war resulted in Georgia's loss of territory in what had been the South Ossetian Autonomous Oblast and the Abkhaz Autonomous Soviet Socialist Republic, respectively, to two internationally unrecognized separatist movements that were supported by the newly independent Russian Federation."
"... the Transnistria War, in which Russian-backed Transnistria managed to stay separate from Moldova."
"The referendum was held under Russian occupation and, according to the Russian-installed authorities, the result was overwhelmingly in favor of joining Russia."
"Intercepted phone conversations of Sergey Glazyev, a top advisor to Russian President Vladimir Putin, disclosed the specifics of the project Novorossiya to take over not just Crimea, but also the Donbas, Kharkiv, Odesa, and Zaporizhzhia regions of Ukraine, which Russia apparently aimed to annex following Crimea. The plan involved fomenting widespread unrest using pro-Russian agents on the ground, and then orchestrating uprisings that would announce rigged referendums about joining Russia, similar to the one that took place in Crimea on 16 March 2014."
This fits the pattern, with the obvious major difference being that Canada is not a former Soviet nation.
Also speculation, of course. But to me it looks like Russia has this strategy which they play over and over, and with which they've been getting more ambitious and seeking larger targets.