The easy way, would be to let AK drive clock and transport.
Then you could go
AK OUT > DK IN
DK THRU > P12 IN
This would let you use the AK to play both the DK and P12, and the DK would sequence the P12
The AK would sequence itself
Another way would be to let DK drive.
AK OUT > DT IN
DT THRU > P12 IN
P12 THRU > AK IN
This should allow AK to play the DK and P12, plus the DK sequencing the P12, and letting AK play itself via DK midi.
You’ll need to find something like a “local keyboards” setting on the AK, you’ll want to turn that off so the notes from your keyboard do not trigger the AK directly, the notes go into the DK and the DK tells the AK what to play.
Of course you’ll need to set up specific midi channels correctly and make sure your clock and transport settings are proper. For now I would not use auto channel, wait till you get this all working.