This is because they get ambushed by assassins, which means The American then has to eliminate the bad guys and the innocent bystander so his cover isn't blown.
After the Interpol convoy transporting Kincaid is ambushedby Dukhovich's goons, Bryce and Kincaid have to work together to get the assassin from London to court in The Hague, so that he can testify before an absurd deadline.