Can anyone help me with the ending, please?

Yes, I am kind of looking for spoilers. Because after watching it twice, this thick set of layers of play, truth, lies, games by the main characters, escapes me totally. The more I watch it, and the more I think about it, the less I see the logic in what the wannabee assassin and his target do towards the end. And those orders given ... I simply don't get the orders given by the Queen to Willenstein that seem to counter the real situation on the ground, then almost a reverse, and yet again, another reverse while the queen is waiting for the man with the shotgun.
Was she intentionally doing some shooting earlier?
And why is the young man interested in the medal towards the end?