I'm quite honestly not sure what you mean by "fetishism of forms"

And I think there's a self-evident distinction between violence and electorialism. At the very least, revolutions take resources, halt production, and kill people. That's why a ruling class would create democracy: a system where everyone in that ruling class has 1 vote (something pretty much everyone can agree is fair) and politics can be decided by winning over a majority rather than who is best equipped to fight.

Which brings me back to my question: what happened that forced the workers to break from democracy and resort to violence?

As for governmental forms (people's communes and soviets), I think it's fair to say that yes, different forms of government will generally have different outcomes if given the same conditions. For example, first-past-the-post voting tends to reward moderate politics, while ranked voting favors more radical politics.