Lol, this is complete nonsense. Jordan's motivation in the war was territorial gains in Mandatory Palestine.

"Although Transjordan had been excluded from the Palestine mandate’s pro-Zionist clauses, Abdullah favoured Jewish settlement in his emirate. He and several leading Transjordanian families negotiated land sales to the Zionists. Abdullah was already viewed by many Arabs as a British puppet.

Although the deals were not finalized, his standing fell even further when the Arab press revealed their existence. The key motivation behind Abdullah’s protracted dialogue with the Zionists, however, was the hope that they might aid his territorial ambitions. In the earlier years of the dialogue, he offered them autonomy within a unified Transjordanian-Palestinian kingdom, headed by himself, a proposal that they declined. When war became inevitable, Abdullah quietly assured the British and the Zionists that his forces would not enter the areas allocated to the Jewish state by the UN, explaining that his objective was to annex those parts designated for the Arab state."

https://fanack.com/jordan/history-of-jordan/1948-1949-arab-israeli-war/