Marc Grossman, the US Special Ambassador to Pakistan and Afghanistan has some major baggage.
On the morning of September 11, 2001, while the attacks were under way, Marc Grossman was in a meeting at the Capitol in Washington DC with Mahmud Ahmed - head of the ISI, Pakistan's intelligence unit, Porter Goss - who later was to be appointed head of CIA by President George W. Bush (only to resign mysteriously shortly afterwards, for no given reason), and Senator Bob Graham, the chair of the Senate Intelligence Committee.
Why is this so weird, one may ask? Well for starters, it was on 9/11. Secondly, Mahmud Ahmed was the man who authorized several international wire transfers of up to $100,000 each, paid to the alleged lead hijacker on 9/11, Mohamed Atta. After the meeting, Mahmud flew straight back to Pakistan, resigned from the ISI and hasn't been in public life since.
In a just world, Marc Grossman needs to be investigated by the FBI. But in today's world. that is like asking the Mafia to investigate John Gotti's activities.