In MI:6 Fallout, Tom Cruise/Ethan Hunt impersonates "John Lark" at the charity event with the "White Widow".
After evading some hit men, the WW tells "Lark" that she is merely a broker, and the real price for the plutonium is for Lark to participate as one member in a gang of at least a dozen thugs in kidnapping Solomon
WW's brother already has a plan in place - divert the convoy transporting Solomon, and ambush them.
Given that they already have a plan, a sufficient number of men, the weapons, vehicles and intel needed to carry out their plan, why would they insist that Lark participate in the act, and consider that as sufficient payment for plutonium cores?
I realise this is an action movie and there is often shaky reasoning for people's actions, but this plot twist completely broke my suspension of disbelief - it makes no sense why they would want Lark (an outsider) to be in the team, especially when they've already planned it all. It makes even less sense that they'd consider that "payment" for something as valuable as plutonium cores. Can anyone offer some in-story reasoning that might back up this part of the story line?