It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that on the day of Khaybar the Prophet (peace and blessings be upon him) "gave two shares to the horseman and one share to the foot soldier."
Abdullah al-Umari makes many errors (kathir al-wahm).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الفيء والغنيمة / 12868