
According to Billi Bhatti on the Dirty Sheets Podcast, WWE had initially planned for Gunther to be the one to retire Rey Mysterio at WrestleMania, adding him to their list of "victims" of ended careers. However, that idea never made it to television because Mysterio already had another ending planned for himself and did not want Gunther to be the one to put an end to his career.
Bhatti explained that Rey made it clear: "I don't want to retire yet, and especially not to Gunther, because my plan is for my son to retire me and do it in Mexico". This refusal forced WWE to find a new direction for Gunther, which ended up with a last-minute program against Seth Rollins instead of the big retirement match that had been considered.
The booking problem didn't end there: after WrestleMania, Gunther was left with very little material despite having already "retired" John Cena, Goldberg, and AJ Styles. Even the favor that Paul Heyman owed him, which originally was rumored to result in a match against Brock Lesnar, did not materialize because Lesnar preferred to continue working with Oba Femi, leaving Gunther out of that matchup.
As a result, Gunther was moved to SmackDown and put into a "forced" program with Cody Rhodes that did not lead him to the title, and then into a feud with Nick Aldis. Bhatti acknowledges that, although they started with a plan B, both Gunther and Aldis have "struck oil" and have built a story that, in his opinion, should lead to a good match at SummerSlam.