To be fair there are other armed groups (ELN, allegedly Wagner, FARC, gangs like Tren de Aragua or Tren del Llano) and they'd surely fight for power. As popular as Edmundo and Maria Corina are among the regular population, if they actually would have the support of the armed forces if Maduro, Diosdado and the military higher ups who run the cartel get churro'd remains to be seen. Allegedly during the election many (low ranking) soldiers protected the people counting the votes and most of the military voted for Edmundo. But of course, it's also true that right now the army is more of a blackmailing gang and repression force than an actual military.
Wagner is only there to protect Maduro and Russian oil instructure. It wouldn't be like Mali/Niger/Sudan where they pick a side and get involved - Russia couldn't force-project to protect Assad Syria and is having to abandon Mali, there is zero chance they'll send significant forces to a Venezuelan civil war. The most involvement you'll see with them is getting Maduro to Cuba, and then making deals with any warlords to ensure combat doesn't endanger Russian infrastructure.
FARC is to disorganized and small to likely play much of a role, and Columbia with a retarded commie at the helm isn't likely to try to use the chaos to "settle border disputes".
The Trens are too small and business-focused to really offer more than a hazard to any deployed military force. They are wealthy and have a lot of violent members, but that only does so much up against even an Latin American trained military force.
They would likely simply back whoever they think is going to come out on top and levy a toll for their assistance, possibly deploy their hitters as supporting militia.
in the event Maduro is Churroed
the sky will rip asunder because the universe is unspoil because the fundamental laws of reality are undone
I don't think we're going to see much organized Cartel-on-Cartel violence so much as intra-Military jockying for the next leader. I'm not read up on how well the Venezuelan cartels interact, but its possible they might use the power shift in any chaos to take out frustrations with rivals, but it wouldn't even be to the level of FARC trying to set up a narcostate.
I don't even think we'd see much violence post a Maduro-churroing. Its more likely the Military will figure out a leader that would be acceptable to Trump, explain to that guy "here are the ground rules on how to not get assassinated" and nothing much changes other than how brazen the cartels are about their operations.
