mmWave Blue switch trailing edge strobing lights with aux

I have an mmWave Blue dimmer 3 way with Inovelli aux switch and 5 led cans that are strobing when put into trailing edge mode.

The switch is wired to neutral.

Leading edge seems to work.

In an other two rooms I have the mmWave connected to the same LED cans, but no aux and trailing edge works fine.

Why is trailing edge not working with an aux?