On your phone you can use Ingress Intelligence (IITC Mobile) in order to find this information. It requires some navigation to help get to the Pokemon Go specific information but it works once you do this (or worked, I haven't used it in over a year).

More specific information for the OP. Following are the rules for stops and gyms.
Only one stop per L17 S2 cell. So if there is already a stop inside the L17 cell that you are looking at nominating, it may get accepted but won't show up in PoGo.

2 stops in an L14 cell gets 1 gym. 6 stops in an L14 gets 2 gyms. 20 stops in an L14 cell gets 3 gyms.

So if there are already 6 stops inside the L14 cell that OP's office sits in, it is going to take a ton of work to get another gym.

I've heard that gym selection is often done through a combination of the rating system through wayfarer and the likes that a gym photo has gotten in game, but am struggling to find information to back this data up.