You are right that the ending was sufficiently open that Vic could be springing Ronnie, or could already be formulating his next move.
Finally, it's worth recalling that HIS main reason for the "money train" was that he had two autistic children to provide for.
Shawn’s fate was predictable—especially in the second-to-last episode when they were squatting in the house and their life was almost domestic bliss; that was pretty much a big neon sign that it would not end well for them. Still, I didn’t expect the whole family to get the Goebbels treatment. That was haunting.