So at this point we all know that the released game was not the "original" game there was a reddit post about the game that the test group played. They claimed the game is 100% different. There was also an easter egg on the first mission. Ever watch the first gameplay showing? They fought a devil walker and the titan had the old vanguard helmet and dark below crucible gauntlets, but that isn't the point. The disabled fallen walker is a reference to how the original game fell and was buried. It took 7 months to remake a new story.