It lies with Haitch.
I'm not sure how that storyline was supposed to benefit Reigns. Let's look at the facts:
1. Reigns loses the title again, just after winning it weeks prior, and does it in the worst fashion. He walked out of his own match even though he was the defending champion.
2. He's randomly given an opportunity to face Haitch for the title again by winning a triple threat match when The Authority should never be doing that considering their hate for him. Combined with him walking out of his own defence due to an "injury", it just makes him look even worse.
3. He defeats Haitch in a traditional wrestling match when he should hate his guts for what he's been through so the match itself should have been a savage brawl.
Now look at the other side of the coin:
1. Haitch wins a second Royal Rumble. He can now add himself alongside the likes of Hogan, Shawn Michaels, Austin, Cena, and Batista as someone who has won it more than once. All bigger stars than him too.
2. Haitch is now headlining the biggest Wrasslin'Mania of all time.
3. Haitch's entire storyline is that he's not afraid of Reigns, and is clearly fine with facing him. Considering he won the Royal Rumble clean, this isn't exactly a good thing when you're trying to make his opponent look good.
4. Haitch tries to put on a traditional wrestling match which does nothing to make Reigns look good. And Reigns is someone who has been putting the best, or near best, matches on any PPV he's been on in about two years.
5. Instead of sticking around after the show, and maybe doing the right thing by letting Reigns kill him a little more definitively, Haitch disappears for several months and only returns to get the title on Kevin Owens.
Nothing about that story seems like it was made for Reigns to come out looking the best he possibly could. It almost seems like intentional sabotage because that's how poorly thought out it is.
If they were really interested in making Reigns look good, then Haitch would've jobbed to him at Royal Rumble and Fast Lane, while Lesnar won the Royal Rumble to set up the rematch. Because really, it's not about beating a B+ player. It's about beating the two top dogs, and right now, those two are Barack Lesnar and Joan Cena. Haitch should've been a stepping stone for Reigns.