But in M-5, their main goal was to kill Yoshiaki Hara for hacking into their system and try to find and kill Sherry. Of course, Haibara made it out alive, even with the bombs blowing the building to shreds. But Hara was killed and all the data he extracted blew up with the skyscrapers.
I'm not so sure how the BO would tie in with a soccer stadium assassination and a bombing, but then again the BO might not even appear.