That's because you are selecting the midi track. You need to select the actual KONTAKT (VST instrument) track. You can't route pure midi to an audio output because it's not an audio channel. Find the Kontakt instrument and expand it's folder if you need to, find the correct channel then set it's output to the group channel.
I also think you meant "route the output" to the group channel (not input) in relation to the track you successfully routed?
edit > beaten to it by one minute.
JUNO 60 | JD-800 | JX-3P with PG-200 + organix mod | SY77 | POLYSIX(x2) | CRUMAR PERFORMER | TG77 | SOFTWARE
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* = Gone, but interesting/recommended synths!