I don’t see how it can be down to interpretation because the law is perfectly clear.
The rule is:
(I added the emphasis).
So the law requires that A player (singular) gains control after it has touched THEIR arm AND THEN creates a goal scoring opportunity.
In other words, for this rule to come into play it has got to be the player whose arm the ball touches that gains control of the ball, and that same player has then got to create the opportity to score or score himself. If the ball had come off Aymeric’s arm, accidentally, but he had trapped it and passed it to Jesus to score, the rule would be engaged. Because the ball touches his arm, but Aymeric does not gain control of the ball, the rule was not engaged. That is according to the clear, unambiguous words of the rule.
The law says nothing about a player from the same team gaining control, and if that’s what IFAB had intended it would have been perfectly easy for them to say so in the new rule. It makes perfect sense to say that an accidental ricochet where a player from the same team is on the receiving end is not the same as that player taking advantage of his own accidental handball. If the rule was ambiguous I can see why you might look at what it designed to prevent to understand what it was supposed to mean, but where the wording of the rule is clear as it is here, you don’t need to go any further than the rule itself.
Face it mate, a perfectly good goal was wrongly disallowed.