Both Te and Se are 6A group elements, that contain 6 valence electrons. By covalent bonding to 4 other atoms, they gain 4 more electrons and thus have 10 electrons or 5 pair electrons in the valence shell. Both TeCl4 and SeF4 cannot be a planer molecule, and thus are polar.
By going through similar argument, we can conclude that (IF4)- and XeF4 are non-polar.
(PtCl4) 2-: not sure.