The factory knock system is not very good, based on what I have gathered it essentially senses a sudden change in noise from a steady state condition. It is tuned to be most sensitive around 6k Hz (natural frequency due to bore diameter), but can be set off by a large enough change anywhere else in the frequency spectrum. You will likely have to go through a number of trouble shooting steps. The fact that you are only getting it when you roll into it may indicate false knock.
When you look at the PL logs, at the point the knock starts check your timing and AFR. If the AXIS has the ability to remove timing in that range pull it back, also make sure the AFR is good in that range, but I don't know the electronics and the sample rate is good/fast enough to narrow down such a specific point. You could really up the fueling, either through the axis, or with fuel pressure to see if it goes away.
One test will not be enough, you will have to hammer it in the trouble spot a few times to verify after changes.
If after altering the timing and fueling in the trouble spot, you can't make it go away, it is likely false knock.
Any source of noise that exceeds the threshold of detection will set off the sensor.
Piston slap, a noisy valve train, loose mounts, accessories/belt tensioner, exhaust or any engine part contacting the frame, a loud transmission, loose balancer, loose flex plate ....