Buy dev product from another place


I’m the developer of a game, which is in someone’s account. For monetization purposes, we want to have the developer products in a group game, so we don’t pay marketplace fee twice. While testing in studio, I could buy the devproduct without an error, but in a live server it gives the following error:
It doesn’t give an error message on client nor server
So the devproduct is in a group game, and I’m trying to purchase it from another game (not in the same group). Is this just not possible, do the group game needs to be public or did I just missed a setting?

Thanks in advance!

It has to be added to the game directly I think.