I believe it currency exchange. Yes. I also think they could be holding onto their own "insurance" policies. NO?
Putting myself in their shoes… I would CMA too. Giving myself the best chance of survival if there is a mission failure.
The cash? No doubt they came by it illegally. Perhaps while traveling to London they acquired a decent sum and brought it home. I wouldn't! The exchange rate is horrible, however, it would depend on the origin.