Character mistake: While posing as Steve's driver, Sameer refers to him as a colonel. He is actually wearing captain's epaulettes.
Character mistake: Chief says the poison gas should be flammable because it's hydrogen-based. Hydrogen is the most common element in the universe, and there are plenty of non-flammable substances that contain hydrogen - the most notable of which being water.
Suggested correction: Hydrogen is explosive in air at concentrations greater than about 4%.
Pure hydrogen is flammable, yes. However a chemical compound that contains hydrogen would not necessarily be explosive, or even flammable. As the original mistake stated, water contains hydrogen and is not flammable. Whilst other hydrogen-containing compounds are flammable (such as hydrocarbons), the presence of hydrogen alone is not the reason for its volatility.