In reality there is only one country between the River Jordan and the Mediterranean Sea. It is called Israel at the moment, which is an apartheid state whose laws privilege Jews over everybody else. Historically, prior to 1948, the only name ever used for all of this territory was Palestine.
He is lying and he knows he is lying. Besides the Kingdoms of Judah and Israel, it was also called Canaan. No one called it Palestine before the second century AD.
The Torah calls it simply "The Land." This pre-dates any mention of "Palestine."
Not only that, but whenever people referred to Palestine before 1922, they meant the lands of the Twelve Tribes of the Children of Israel. The word "Palestine" in the vernacular meant the areas controlled by Jews in Biblical times - including parts of today's Jordan.
Winstanley is an idiot.