You are extremely fortunate. The man I knew was a Marine. The battle lasted over 20 days. The flag raising in the picture was the 2nd flag. I believe the 1st is in the USMC museum. Cherish your time with your friend. Not many of those men from WW2 left.
When he was on Tonga his hand got an infection and he was sent to the hospital ship USS Solace. Interestingly, my father-in-law was a pharmacist mate on the Solace. He’s 96 and just gave up cross country skiing.