If you have a raw kiss frame you should see e.g DB C0 id a byte that has an real value of C0. In this case the C0 is not the frame end.
DB DC is a real byte value of DC and not TFEND.
Abbreviation Description Hex value
FEND Frame End C0
FESC Frame Escape DB
TFEND Transposed Frame End DC
TFESC Transposed Frame Escape DD