You don't need a full on PC for 4k. A Raspberry Pi 4 with LibreELEC installed will render 4k just fine whether the file is on the SD card locally or...
Could it be that it had a Lexmark toner cartridge installed, not a Toshiba cartridge? Or vice-versa? I'd think the EEPROM would be coded differently....
There certainly isn't a lot of detail in that bulletin. It would have been nice to know what changed. Or would that be too much like admitting there...