You would have to read those two reports to learn more, but unlike UNHCR, UNRWA does not have a mandate to resettle Palestine refugees and has no authority to seek lasting durable solutions for refugees.

A syrian refugee can be repatriated, a Palestinian refugee will stay a refugee

It has to do with denying Palestinians Right of Return

https://academic.oup.com/rsq/article/28/2-3/229/1584825

https://reliefweb.int/report/occupied-palestinian-territory/exploding-myths-unrwa-unhcr-and-palestine-refugees

That’s not how genocide works and this is asymmetric warfare of an occupying force onto the occupied, not a normal war. The south africa case is very detailed and explicit about each five points in the genocide Geneva convention.