It looks like Red Dead Redemption 2 would actually be called Red Dead Revolution and that RDR2 would feature John Marston's son, Jack, as the protagonist if the reports and rumors are to be believed.
Suresh Gupta of GameKlan has reported that Rockstar's next Red Dead game would be allegedly called Red Dead Revolution instead of Red Dead Redemption 2, however, the game would be tied to Red Dead Redemption.
Previously, we have reported that Cyberland has reported that Rockstar is working on two games right now, GTA 6 and Red Dead Redemption 2 (working title). They reported that Red Dead Redemption 2 is going to follow the story of Jack Marston. Cyberland noted that the Red Dead franchise is going to differentiate itself from the GTA series by making the games' story connected with one another unlike the GTA franchise.
Cyberland has reported that the next game in the Red Dead game franchise is going to the PS4, Xbox One and PC unlike Red Dead Redemption that was only released on the PS3 and Xbox 360.
It should be noted that earlier this year, VG 24/7 has reported that Red Dead Redemption "appeared on a database made by Microsoft to help in determining application compatibility with its various operating systems."
According to the report of VG 24/7, The Red Dead Redemption PC version was shown with various compatibility statuses for Windows 7, 8 and 8.1.
Game Rant posted a screenshot of the Red Dead Redemption PC version on Microsoft's website as seen below: