The casualty numbers I found for Iwo are a little different.
Total Losses
U.S. personnel 6,821 Killed 19,217 Wounded 2,648 Combat Fatigue Total 28,686
Marine Casualties 23,573
Japanese Troops 1,083 POW and 20,000 est. Killed
the article is saying 26k killed for US troops, it should read 26k casualties.