Character mistake: When Guile promises to rescue the hostages while on camera with Bison, he makes it a point to mention Charlie by name to reassure him that he wasn't forgotten. Anyone in charge of a major hostage recovery operation would avoid naming a specific hostage unknown to the enemy due to the special focus that the enemy may put on that hostage for further abuse. This was promptly proven when Bison specifically chose Charlie to transform into a beast due to Guile identifying him as a personal friend.
Character mistake: A character mentions carbon-dating one of the fossils found. This is preposterous... you can't carbon-date fossils like the ones being shown. Radiometric dating maybe... But certainly not carbon dating. He's a professional and should know more than better that carbon dating wouldn't work.