YOU SAID:
Wouldn't letting him live for the rest of his life as an 'outsider' while everyone lives happily around them be just the perfect punishment for the torment he caused?
INTO JAPANESE
誰もが彼らの周り幸せ生活中「部外者」として彼人生残り部分ために生きる彼をさせるだろう彼引き起こされる苦痛ための完璧な罰だけか。
BACK INTO ENGLISH
Everyone around the happy life in their as an "outsider" he life rest for will let him live caused him pain because of or just the perfect punishment.
You've done this before, haven't you.