Frankly, there's no other explanation for it. The legal principles at play in occupied Palestine are so abundantly clear and well known, at least to the executive of this country, because we wax lyrical about them when it comes to Ukraine: the inadmissibility of acquisition of territory through force, the right of peoples to self-determination, and so on.
To my mind, either folks at GAC or in the PM's office don't know the law, that same law, as it applies to occupied Palestine, or they are otherwise playing at something altogether different, and that is being selective with international law when it serves our purposes as perceived by our government, and claiming otherwise, that we have a fidelity to it across the board.