TTIG connect to Open source stack


I have a TTIG (The Things Indoor) Gateway that is claimed on The Things Stack community edition. I would like to connect it to my private Things Stack Open Source.

I’m following this documentation : The Things Indoor Gateway | The Things Stack for LoRaWAN
I created an API key in my private instance. Then, I configured on TTS CE gateway parameters (in general settings) as follow :

Unfortunately nothings appear on my private instance.
I’m wondering if it’s possible to connect a TTIG to a private Open source stack?

Thank you.