Bruce had learned through the Battleworld channel that Batmen from other universes were all developing magic, each faster and more competitive than the last. His own universe was already facing disaster. If he did not take a few shortcuts now, he would never catch up.
Perhaps to support a less advanced universe, Main Universe Batman had hinted, openly and covertly, at who the biggest and easiest target for Shear wool in the Single Universe currently was. Bruce naturally accepted the favor without ceremony and set his sights on Mount Olympus.
So far, every Batman who had made a move against Mount Olympus had succeeded. It truly was a fat sheep anyone could shear. But an older Batman was indeed more particular about such matters; he wanted legitimacy and a proper justification.
Never mind who caused the explosion, and never mind why the Justice League had appeared on Mount Olympus. The fact was that Justice League members had been present around an explosion powerful enough to destroy an entire temple. It happened on your territory, Zeus, so you had to take responsibility. Humanity was going through troubled times and had no time to deal with you for now. Once Batman freed up his hands, you would surely have to contribute to humanity's magical defense network.
In short, it was a plan that killed three birds with one stone. First, it eased Diana's heartache and at least let her see her sisters again.
Then it allowed Victor to absorb the Mother Box held by the Amazon queen as a matter of course. That had not actually been easy. With ordinary methods, it would likely have been impossible, since it was someone else's property, not something they could simply demand.
Although Diana had made the move this time, the Amazon queen had not