Nuki Opener generic bus with relay

I am considering to buy a Nuki Opener to be used for a “garden door” that is a door outside in the street to access the garden. Unfortunately, my intercom is a Fermax Duox (digital bus) that is not supported due to the fact that to open the door the connection must first be established (letting through the ringing bell or pressing the video button). However, I actually don’t nmeed the Nuki Opener to unlock the door.

I live in a single-family house and therefore have full access to the complete installation. I have therefore installed a relay (Shelly 1) directly behind the Fermax panel (ring button) in the street that allows me to unlock the garden door via e.g. Home Assistant.

I would like to be able to use the Nuki Opener with Ring-To-Open mode set whenever I arrive close to home and use the bell from the Fermax panel to unlock the door without the bell actually rining in the intercom system. What I would therefore need is the Nuki Opener to simply intercept the bell signal when it is pressed in the Ring-To-Open mode. I don’t care if Nuki Opener thinks it opens the door without doing it as I would use a callback to check an event that the button was pressed and therefore just activate the relay to unlock the door.

The important part is that Nuki Opener can suppress the bell when in Ring-To-Open mode, while leaving everything as is (so the intercom should otherwise still work as expected, e.g. I can press the video button to get a picture and audio from the camera of the Fermax panel in the street, etc.).

My question therefore is if you believe that I would be able to use the Nuki Opener to intercept the bell ringing? My idea would be to install it as shown in the picture and from your documentation for “generic bus” here: https://support.nuki.io/hc/article_attachments/4417715168401/howtoguide_opener_EN.pdf
Or should I install it differently?

Can I train the Nuki Opener to intercept the bell without having the opener functionality working (e.g. skip the opener functionality within the training in the app)?