In the digital input case, the data stays in digital domain into the graph analysis. For that reason, as long as jitter does not cause data drops, it will never appear.
In contrast, when fed to a DAC and its analog output is analyzed, jitter can modify the DAC clock, reference voltage, or its analog output, all of which shows up in the FFT.
In other words, in digital audio, the only time jitter is a performance problem is when we convert it to analog. As long as it says in digital domain, it doesn't matter. The traces in your computer for example have jitter. Yet moving data around there is immune to such interference (again, until it causes data errors).