When the switch is in 3-way toggle mode, the aux switch turns the master switch on and off, but it does not change the load. I can hear the master switch clicking, the LED turns on and off and the state is updated in the hub, but the load stays off.
When the switch is in 3-way momentary mode, the aux switch can turn the load off but not on. When it turns the load off, the LED on the dimmer goes to its off setting and the state is reflected on the hub, but I do not hear clicking. Once turned off with the aux switch, the aux switch isn’t able to turn the light on.
It is a GE 46200 and I know it is not on the tested list but it worked before 1.55 when set under 3-way momentary.