I think it was planned exactly like that. Alvarez has been talking all day about how Orlando is NXT territory and the people there love Triple H, if it was down to Reigns and him it hurts the case for a rematch because Hunter would have won clean and at the same time the fans would have cheered. They want Triple H to go out as the heel and Dean was a safe bet to be super over with absolutely everyone live and at home.
Ya it was to smart to be a in match call. I imagine they expected Roman to have a bad reaction, but not as bad as he got. Still they knew HHH was going to lose his heel heat when he tossed Roman so they needed a face to get it back. Was pretty perfect booking to do what they wanted to.
Almost everything was booked pretty perfectly. How they got AJ out, how they got KO out. Booking of the Wyatts. The two **** ups was Roman walking to the back (either stay on the stretcher or walk back into the match. Jesus christ) and Brock leaving without a murder rampage (Dolph should of been killed on the ramp).
Like I said above. An audible would of been them seeing how insanely over Styles was and pushing him into the final bunch, and deciding lets get HHH some nuclear heat and eliminate Styles.