It must receive certification by the Domestic Relations Court. It has a valid date later than the one addressed to Kiyoe-san... ...and, in addition, this Will has validity by being in his own handwriting.
家庭裁判所の 検認を 受けなければ なりませんが→ 清江さん 宛てのものが 有効である 以上→ それも 自筆 証書 遺言としては 有効でしょう。