（子が突然拉致され）再び会う事なく他界した彼の無念は計り知れない、と言いたいです
It is sad to see him pass away without ever seeing his daughter again.
We will never know how he was feeling inside.
(He) passed away without being able to see his daughter again.
The regret he felt is immeasurable / you can’t imagine the regret he felt.
この文章が以下のように翻訳されています。
息子と再び会う事なく他界した ー (He) passed away without being able to see his daughter again.
彼の無念は計り知れない ー The regret he felt is immeasurable / you can’t imagine the regret he felt.
参考になれば嬉しいです。
オーストラリア 
