At first, he promised to give 100 million yen to people who retweeted at random. But, he finally gave it to people who retweeted their dream or would use it for charity.
people who retweeted their dream, or to those who said they would use it for charity
質問者様の文章で通じると思います♪
指摘するのであれば、この短い文章で唐突な finally が不自然かもしれません。
この場合は「最終的には」というニュアンスの “ended up” がいいのではないかと思います。
At first he promised to give 100 million yen to random followers who retweeted his tweet. But he ended up giving it to people who retweeted their dream, or to those who said they would use it for charity.
He chose people who shared their dreams or would use the money for charity.
・He chose people who shared their dreams or would use the money for charity.
彼は夢を共有した人や、お金を慈善活動に使う人を選びました。
・He picked those who talked about their dreams or planned to use it for charitable activities.
彼は自分の夢について話した人や、慈善活動にそれを使う予定の人を選びました。
英語で「〜する人を選んだ」と言う時は、「chose people who...」や「picked those who...」を使って説明するのが自然です。
日本 
アメリカ合衆国 
