Ṭibāq rests on the presence of opposed meanings, such as life and death. Tafrīq does not require words to be lexical opposites. Its basis is a shared type combined with a rhetorically marked distinction.
FigureBasisTypical effect
ṬibāqOpposed meaningsBright/dark
TafrīqDifference within one categoryComparing two gifts
Both figures can coexist. But a difference is not automatically lexical opposition, and two antonyms alone do not satisfy the technical condition of tafrīq.