When travelling from London to Paris, a UK Border Force agent scans his passport. This wouldn't happen, as when leaving the UK, the Border Force don't check passports. Notification of departure is done through the boarding pass or train ticket. French border police would've checked his passport at St. Pancras, granting him entry into France.
Sarah says she'll "take the overnight back from London." Actually, the overnight flight is from the US to London (eastbound) and the flight from London to the US (westbound) is all the same day, not overnight.
In response to a puzzle from another character at lunch, the main character stated that the White House Christmas always come from Leighton, PA. It has come from there, but it comes farms across New England and other part of the country. It doesn't always come from there.
When flying to London, an Airbus A380 taking off is shown while the flight crew welcome announcement says "Welcome to your American Airlines flight AA 143".
American Airlines doesn't operate any Airbus A380.
Flight AA 143 is actually a flight from LAX to Honolulu.
Romanian number plate format is AB12ABC except the capital Bucharest which is A123ABC, the van used to collect the missiles had wrong plates.
When Heller arrives at St Pancras station in London it shows the coordinates 51°31'48.7"N 0°07'29.4"E, which is 13 miles from the station.
After discovering that the main character had absconded from the training facility, the CIA could have put a notice on all possible passport aliases so that he is picked up either when departing or arriving via the airport. The dialogue indicates that they were convinced he was bluffing about the 'dead man's switch' so it would have been logical that they stopped his travel and had him apprehended.
The name Mishka Blazhic is not a specific Belarussion name. Instead, the name Blazhic (in neoltain transilateration) is specific for the Slvas form the South: Serbs, Croats a.s.o.