How sound is the Hadith: "When Allah opens Egypt for you, take from its people a dense army, for they are the best soldiers on Earth, and they are in ribat until the Day of Resurrection"?

No one has attributed the aforementioned Hadith to the books of Hadith. Al-Sakhawi mentioned it in Al-Maqasid al-Hasana with its exact wording. Sheikh Muhammad bin Darwish al-Shafi'i stated that nothing authentic has been reported regarding the virtues of Egypt. Al-Ajlouni, in Kashf al-Khafa, mentioned Hadiths concerning the virtues of Egypt and judged some of them to be fabricated or severely weak.