The opening scenes are set in AD 1109. Later, in the staff meeting, this is referenced as the 11th century instead of the correct 12th century.
Apparently some (or even all) of the people at the lab have the same ID number.
One of the warriors in A. D. 1109 brings what is apparently a barrel of gunpowder to the cave. Gunpowder did not appear in Europe until the late 13th century.
There is a fusion explosion in the lab, with power half the Hiroshima bomb. After it's exploded, rescuers find another lab just 30 meters below explosion point. The lab is still quite operational, and even the second dragon is alive and well.