It turns out that he floated this theory decades ago, and has written a number of books on the subject.
According to Wikipedia,
Kamal Salibi has written three books advocating the controversial "Israel in Arabia" theory. In this view, the placenames of the Hebrew Bible actually allude to places in southwest Arabia; many of them were later reinterpreted to refer to places in Palestine where the Hasmonean kingdom was established by Simon Maccabaeus in the second century BC.So if the Jordan of the Bible is proved to refer to a river, his entire thesis gets destroyed, right?
The (literally) central identification of the theory is that the geographical feature referred to as הירדן, the “Jordan”, which is usually taken to refer to the Jordan River, although never actually described as a “river” in the Hebrew text, actually means the great West Arabian Escarpment, the Sarawat Mountains. The area of ancient Israel is then identified with the land on either side of the southern section of the escarpment that is, the southern Hejaz and 'Asir, from Ta’if down to the border with Yemen.
Joshua 3:15-17: And when they that bore the ark were come unto the Jordan, and the feet of the priests that bore the ark were dipped in the brink of the water--for the Jordan overfloweth all its banks all the time of harvest-- that the waters which came down from above stood, and rose up in one heap, a great way off from Adam, the city that is beside Zarethan; and those that went down toward the sea of the Arabah, even the Salt Sea, were wholly cut off; and the people passed over right against Jericho. And the priests that bore the ark of the covenant of the LORD stood firm on dry ground in the midst of the Jordan, while all Israel passed over on dry ground, until all the nation were passed clean over the Jordan.Also, 2 Kings 6:2-6.
2 Kings 2:2-3: And fifty men of the sons of the prophets went, and stood over against them afar off; and they two stood by the Jordan. And Elijah took his mantle, and wrapped it together, and smote the waters, and they were divided hither and thither, so that they two went over on dry ground.(also see 2 Kings 14-15)
2 Kings 5:10-14, And Elisha sent a messenger unto him, saying: 'Go and wash in the Jordan seven times, and thy flesh shall come back to thee, and thou shalt be clean.' But Naaman was wroth, and went away, and said: 'Behold, I thought: He will surely come out to me, and stand, and call on the name of the LORD his God, and wave his hand over the place, and recover the leper. Are not Amanah and Pharpar, the rivers of Damascus, better than all the waters of Israel? may I not wash in them, and be clean?' So he turned, and went away in a rage. And his servants came near, and spoke unto him, and said: 'My father, if the prophet had bid thee do some great thing, wouldest thou not have done it? how much rather then, when he saith to thee: Wash, and be clean?' Then went he down, and dipped himself seven times in the Jordan, according to the saying of the man of God; and his flesh came back like unto the flesh of a little child, and he was clean.
Guess Salibi wasted a few decades of his life. Oh, well.