For a moment he had a fleeting picture of the strange glamour that had once invested the beaches. but the island was scorched up like dead wood – simon was dead – and jack had… the tears began to flow and sobs shook him.

died

Explanation: Simon was dead, and Jack had died. 'Was' is a past continuous tense word showing an action that had been performed moments, seconds, minutes or even years ago, and that action or event will continue to be in the past. 'Had' on the other hand is showing an event that just occured recently. Simon might have died 2 days ago and Jack's death might have come seconds ago.