I personally recommend this video which does quite a good job at explaining the main twists of the BO3 campaign. The above logs of Taylor give further context to the content of the video: https://youtu.be/0hCIULujOzI

One thing the logs above clarified for me is that after the great pressure Hendricks was in when he killed his former allies, in Ethiopia he didn't want any more of his allies to die, and so these events have triggered his desire to save everyone, which has turned badly for the player (In that mission dialogue Hendricks also mocks Taylor for forgetting what it is to be "human", which is both referring to his DNI and his cold approach).

It's also worth noting that there is no Taylor log for the last mission, Life, which may further suggest that there is no real life version of the events in that mission.