The meaning of 段階で揉める

Question

「そこで、まずは世界を望み通りにしたいと言えばよいのじゃ。実際にどうしたいかは後で考える」

「そういうのもありなのか……」

「試練を乗り越えたその時に、エストが望む世界に変えられよう……王も、国も、アルマとやらもしたいようにするがよい」

「望み通り……か」

「うむ、望みは具体的でない方が得策じゃ」

「家族に結婚を認めさせようと挑んだカップルが、冒険している内に冷めきって、願い事の段階で揉めるという事案もあるしのう」

Context:

1. Before one begins their trial they must state their wish
2. One must find a 霊王類 who can allow them to begin their trial(if they are suitable)

My question relates to the meaning of the last part of this excerpt as I don't quite understand. The stages are that firstly one must find a 霊王類, the 霊王類 then calls a God who asks them their wish, and finally they are given a trial by the God to complete and if they do this successfully their wish comes true. From how I understand 願い事の段階, it would suggest that this is the "stage" at which the couple come to a disagreement(i.e Having lost their "passion" for one another over the course of their Journey, they no longer want to wish for the same thing and naturally trouble occurs when they have to decide on something to wish for.). I don't really see the big deal here as it would (hopefully) be easy to come to some agreement about something else to wish for that would satisfy them. In this case, it would just be making the point that things are much easier if you are less specific in what you wish for as you will not necessarily want the same thing now as you do in the future.

But the above doesn't quite sit right with me. If I was to understand this as saying that after they had made their wish and were in the process of completing their trials they had lost their "passion" for one another then it would make a much better argument as it would make clear the importance of not being overly specific with what one wishes for, since if you no longer want it, you are not going to be very motivated in completing your trial. Only problem is that this doesn't seem to be at the 願い事の段階 and rather at a different stage.

Can anyone clarify as to what Xの段階で揉める means (e.g. does it mean that at stage X of some process, arguments,disputes etc occur, or does it refer to the topic that causes these problems etc), and secondly , how do you understand the last part of the excerpt 「家族に結婚を認めさせようと挑んだカップルが、冒険している内に冷めきって、願い事の段階で揉めるという事案もあるしのう」.

Answer 1

This 願い事の段階で means 願い事を述べる段階で, or "at the stage where they (=couple) state a wish (i.e, after finding 霊王類, before the trial given by the God)". 願い事 literally means "wish", so there is no ambiguity in this phrase.

Does a challenger really has to state his/her wish before the trial of the God? Then this 挑む in the sentence in question refers to starting the journey to meet 霊王類. And 冒険している内に refers to that journey (again, before they could meet 霊王類). Maybe this couple even did not start the trial of the God.

This couple had lost their "passion" during their long 冒険, but somehow managed to find 霊王類. Maybe they had been pretending to be getting along, and secretly thinking of betraying each other and wishing something else.

• 家族に結婚を認めさせようと挑んだカップルが
  The couple which started their challenge (ie, to meet 霊王類 and pass the trial),
• 冒険している内に冷めきって
  ... lost their passion during their journey to meet 霊王類,
• 願い事の段階で揉める
  ... and argued at the stage of wishmaking (before the trial given by the God)