I would truly source other MIDI cables first as it would be very rare an unlikely that its the kemper.
+1
I cannot remember, that we ever had a defect MIDI connector. At this point we don't know yet, if the FCB 1010 isn't sending, the cable isn't transmitting or the Profiler isn't receiving, but there is high probability it's a cable-problem and it's the easiest to fix.
As soon as the Profiler detects Uno4Kemper you will see a confirmation on page 6 of the System menu.
Assuming that one cable is defect, you could perform the following test: Just test ONE cable after the other to connect the FCB 1010 MIDI Out with the Profiler MIDI In. No cable should be connected from Profiler MIDI Out to FCB 1010 MIDI In. This should enable a backup mode with limited functionality. The Profiler doesn't recognize, that Uno4Kemper is connected, but receives and executes MIDI commands. You should be able to control Volume and Wah via pedals, if the FCB 1010 had been calibrated before. If this should work with one cable and doesn't with the other, you will have identified the defect cable.