So you have a GMB listing that shows up in the 3 Pack for one GMB category, which means you have more more relevance, better proximity and better prominence than most competitors. Yet you don't appear for other categories even though you have relevance and proximity and think you have good prominence for that additional category.
Assuming prominence is the strong enough how do you improve your prominence for that category to Google? (Please do not say keyword stuffing in the GMB business name).
I have a client experiencing the same issue. When I google their other business name, a business from a different country with the same name shows up on the right hand side listing. Is there anything that can be done to increase their "prominence" or "authority" such that when they are searched locally, their business shows up and not one another business from a different country?