this song was recorded in several takes. i don't remember the source for the information, it was an interview or candid comment made by someone involved in the recording process. maybe the outlawz. basically, he re-wrote the song several times. i don't think the final version is a song that was recorded in one session. i think several versions were recorded, then they pasted the best parts together and finalized it. that's more of a personal theory though.
the original version is not in fact an original version. imagine if you have a 3 hour studio session. at the end of the session you have a final track. if you could tap in at 1hrs 16minutes or 2hrs 28minutes and save the most current mixdown of the song at that point, you would get a "unique" mix. whether you want to call it an original version or not is up to anybody really, but per definition it's not an original version.
i think this is the case for a lot of the "alternate versions" of originals we have. one if a final product while the other was recorded before the studio session was finalized.
edit: just to be clear, i think the original version leak we have is indeed the original version of the song, but it's not the finalized version of the original version. it's a technicality but if you wanna be the big 2pac ogs collector and talk like you know shit you have to come correct ;p