Nonsense. The Syrian army committed 1,500 men. They were wholly unprepared for the war, having received notice that they were to fight just a few days before the 15th of May. Their logistics were poor - they had handed over a part of their munition reserves to the Arab Salvation Army, and given its scarcity of war matériel had to husband what was left. Its knowledge of the theatre of war where it was to conduct operations was minimal. It took then almost a week to get their tanks over the Jordan. Their first advance was roundly defeated, with heavy losses. On the 18th under Husni Zaim they attacked and took Samakh, south of Tiberias, only to lose it in three days after an Israeli-kibbutznik counter attack. This massive army 'with artillary, tanks, (armed?)armoured cars and airforce stocked with Harvards, (not Harvard-armed aircraft!!, which is a brilliantly comical image)' took 4 days, involving almost all that the Syrian army could muster, to capture a little  moshava like Mishmar HaYarden, with its 20 local guards (Tal p.261) which had to fight on its own, without IDF assistance.
Secondly, you really should stop this nonsense about RS bias. Morris is biased against the Palestinian/Arab side, anyone can see that, but he is eminently good on the facts. Laurens is perhaps the most neutral of all, but he gives the Arab version a much more intelligent coverage than others. Morris, Tal, Gelber, Laurens are all RS, and that's all that counts. One cannot challenge one of them, as if the others were somehow engaged in 'neutral' coverage.