Unable to include Donexon varmo TZ pro

I have got 2 Donexon varmo TZ pro thermostates, which looks exactly like my devolo which i already use for a while.
I tryed multiple times to include, but with no luck.

I followed the instructions from here:

When i press the button, it starts flashing, but nothing happens. I see some of my devices communication when i watch the log during inclusion, but nothing from the new device.

The termostats are clearly the z-wave version, since there is also a proprietary one available), because it has the z-wave sticker on the cover and on the package.

My Home Assistant is running on a raspi with a Silicon Labs 700 series Z-Wave stick. And it works perfectly with all of my devolo thermostates.

Im using Z-Wave JS UI on my Home Assistant…

Any suggestion, how to get these thermostates included?

… i also tryed exclusion