I don't know myself.
The dimmer needs to be probed.
Seems obvious that it is fed 12V from one of the drivers and converted..
Just check the voltage going back to the driver for dimming. Need to set the pot at 100% output.
Historically they have used 5v pwm, 10v pwm and 10v analog.
5v pwm (maybe 3.3v?) seemed to have been reserved for the "programmable" ones not usually the manual dim type.
Converting the Apex from 10v analog to some form of pwm isn't the "usual" direction

Going 5 v pwm to 10v analog for the meanwell dimmers is more common.
Steves "thing" may work fine..
No they are dimmable