Most of that TSB was to address the change in the mid 2000's by Hyundai/KIA that had their newer models that would pressure spike with then current filters like the FRAM PH3593A could not handle it and why they came out with the PH9688. Other filters makers had to change also and some did not.
It also adds confusion that some private label oil filters that used the FRAM numbering system like this Champion CS3593A still using the old FRAM base part number.
Lastly, that TSB also does not explicitly prohibit all aftermarket filters for Hyundai/KIA but just gives the dealership tech guidance that if they are presented a vehicle with a problem aftermarket oil filter, the visit is not covered under warranty if the remedy is to install a OEM oil filter.
As to Champion (not Champion Labs) oil filters, the only retail place I ever saw them was Pep Boys and they have been out of the retail parts game a few years now.