You seem to be missing a key point: acquisition of territory by force as a result of a defensive war is completely legal under international law.
The 67 War was a preemptive défensive war. Egypt had ordered UN troops out of the buffer zone in the Sinai, massed troops at the border, and had blocked Israeli shipping in the Gulf of Aqaba and the Suez Canal.
Meanwhile Jordan launched attacks on Israel despite Israeli pleas for Jordan to stay out of the war.
In the days before June 5, Jordan had deployed in the West Bank opposite Israel ten of its eleven brigades, totaling…
Jordan had illegally occupied parts of Judea and Samaria and was the aggressor in the 67 war. On that basis alone the Israeli claim to the land is fully legal. Israel is no more an occupier of Judea than France is an occupier of French land conquered back from Nazi Germany after WWII.