I don't get this idea that it wasn't supposed to happen.

Then you aren't paying attention.

When he was "fired" he was allowed back to the indies until the heat died down then brought back for the second biggest PPV of the year, in the biggest match.

You don't need the quotation mark as he was legitimately fired. WWE had no control over the bookings he took after he was fired so I don't understand your use of "allowed". Vince did not want to bring Bryan back so Pat Patterson tried convincing Vince but Vince said no. Afterwords Cena stepped up in favor of bringing him back and was able to persuade Vince.

He was given the US title, Money in the Bank then the WHC within the space of a year.

Bryan said that his winning of the WHC was accidental. Bryan also said that the reason they had him lose to Sheamus in 18 seconds was because they wanted to give Sheamus a huge push.

He was given the biggest storyline of 2013, fighting the authority.

Cena was injured so they decided to give Bryan a try since he was the second most over face. But Stephanie admitted that after the SS buyrate came in they soured on Bryan and decided that he wasn't going to hold the title. That's also why they halted the feud and ended up putting Big show in his place, yes chants included. Of course that's also why they stuck him with the Wyatt's for a few weeks and why they didn't bother putting him in the rumble.
Bryan has confirmed on multiple occasions that he wasn't supposed to main event WM, and that he was slated to face Sheamus instead(Just like Meltzer said back in January 2014).

I don't believe that WWE do not know what they are doing with Daniel Bryan.

Then please explain the 18 second loss and all of the inane booking that took place after SummerSlam. Also explain why you think Stephanie, Bryan, and Meltzer are liars.