If the trace of janabah is found on clothes, and it is not possible to distinguish between maniy and madhiy due to their mixture, is that considered ritually impure or pure, knowing that maniy is pure and madhiy is impure?

The wetness after sleep has several possibilities: it could be madhy (pre-seminal fluid) or maniyy (seminal fluid). The emission of maniyy does not necessitate the presence of madhy with it; if desire intensifies, maniyy is emitted without madhy. If you confirm that madhy was expelled along with maniyy, the garment becomes impure. As for maniyy, it is pure according to the preponderant opinion, but it is better to wash it from the garment and body to avoid scholarly disagreement.