User blog comment:MakeShift/The Crisis and its impact on the Arrowverse Wiki/@comment-34482890-20200202164404/@comment-34482890-20200206001613

The way I interpreted it, the Pre-Crisis Titans Earth included the original, scrapped Season 1 finale (as the Pre-Crisis cameo used footage from that scrapped finale), while the Post-Crisis Titans Earth followed the path of Season 2 of Titans, (as most of the Post-Crisis cameo footage came from Season 2).

Now I know this isn't really supported by anything, but it's just a theory I'm quite fond of.