It's... a little complicated. Sorry, saying 1 wasn't exactly clear -- Red Dead Revolver is a precursor to Red Dead Redemption, so they are different games.

Revolver was released in 2004 and is a smaller game, featuring a different character, referenced in newer games as an Easter egg. It actually was a partnership between Capcom and Rockstar, with Rockstar finishing the game after they bought the rights.

Red Dead Redemption was in 2010 and is larger, it also had the DLC Undead Nightmares released.

And then Red Dead Redemption 2 is obviously the followup to Redemption 1.

I think the best way to look at it is from the in game narrative, the gameplay of Revolver is a retelling of the events which have been greatly exaggerated after becoming a legendary story. Which is why the references to Revolver in the later games are like tall tales.

Anyway, long story short, no not Revolver. What just came out is a rerelease of Red Dead Redemption 1 and Undead Revolver, the 2010 game.