McGarrett and Junior go to Nigeria to rescue McGarrett's mentor Joe White. The three men find shelter in tunnels before the building they are in is hit by missiles. They can't go back the way they came in because of the destruction. They are seen heading to an alternate exit showing daylight, but they don't know if the enemy is there, or rescuers. The scene changes back to Hawaii and the other members of 5-0. Soon after, McGarrett and Junior are back in Hawaii with no explanation of how they were able to leave Nigeria.
At one point, Kamekona talks about "the ancestors of the original owners" getting back possession of the works of art that belong to them. That is not correct. What he clearly meant was that the art works be returned to the descendants of the original owners, and not to the ancestors.
When Steve and Junior are in the mission with the SEALS they address him by his name over comms this would not happen for security reasons.