I am aware that if people left Shul in middle of Chazoras Hashatz and there is no longer a Minyan, we may finish Chazroas Hashatz and also Kaddish after U’Va L’Tziyon. My question is can we also say the other Kaddeishim, or it only applies to that one Kaddish?

The Kaddeishim after Shir Shel Yom and onward are not considered גמר תפלת י”ח (“the culmination of Shemoneh Esreh”) and therefore should only be said if there’s a Minyan present during the recitation of Kaddish.