Tricky Temple Mount Two-step

Pay attention:

The Moslem Conquest of Jerusalem - In 638, following a protracted siege, the residents of Jerusalem surrendered to the Caliph Omar ibn Khattib. Accounts of the actual surrender vary, but both Christian and Moslem sources describe Omar entering the city dressed in a simple camel hair cloak and presenting its residents with a letter of protection. In this letter they were guaranteed protection for person and property under the condition they pay a tax, (levied as form of humiliation on "protected" minorities), known as Jiziya. The early Arab historian Tabari claims that the original letter of protection included a prohibition on Jewish residence in Jerusalem, however this seems unlikely given that other sources mention Omar seeking Jewish advice on matters dealing with Jerusalem.

The Temple Mount Transformed - Omar recognized the sanctity of the Temple Mount, perhaps at the behest of his Jewish advisors. Shortly after his arrival in Jerusalem he cleared the site of refuse, apparently with the aid of Jewish workers, where they came from is uncertain, and planned to erect a large mosque at its southern end. Among Omar's close advisors was a converted Jew named Ka'ab El Akhbar. Ka'ab proposed that the mosque be erected on the northern side of the Temple Mount so that worshipers could face both the Foundation Stone and Mecca simultaneously. Omar rejected the proposal as an attempt at "Judaizing" Islam and the Mosque was subsequently built in the south, where the present-day El Aqsa stands, an effectively forcing worshipers to, literally, turn their backs to the Jewish holy place. From this it may be deduced that Moslems hadn't yet associated Jerusalem and the Foundation Stone with the "Night Journey of Mohammed".

Here, too:

Building of Al-Aqsa Mosque - Kaab accompanied Khalif Umar in his voyage to Jerusalem (Al-Quds) He helped locate the foundations of the ancient Jewish temple where Umar built the Aqsa Mosque. He also helped later find the place of the Rock while he was looking for the Holy of Holies. Umar cleaned it from rubble and fenced it and an Umayyad Khalif later built the Dome of the Rock over it as an integral part of the Aqsa Mosque.

Even at Fodor's they know this:

When the Arab caliph Omar Ibn-Khatib seized Jerusalem from the Byzantines in AD 638, he found the area covered with rubbish and had to clear the site to expose the rock. It is said that Omar asked his aide Ka'ab al'Akhbar, a Jewish convert to Islam, where he should build his mosque. Ka'ab recommended a spot north of the rock, hoping, the story goes, that the Muslims, praying south toward Mecca, would thus include the old temple site in their obeisance. "You dog, Ka'ab," bellowed the caliph. "In your heart you are still a Jew!" Omar's mosque, south of the rock, has not survived.

^