Question about "Finders Fee"

[Erin McIntosh]

Hello, 

I've recently rented out one of my properties to a single family. I normally rent to students so I usually find the tenants. This time, I used my agent to help me find a tenant. I also posted my listing on Zillow, just to broaden our search. 

The agent of my new tenant, saw the listing on Zillow, but instead of contacting me through the listing, he contacted my agent, as he was the one that also sold us the house. 

Long story short, the new tenant was able to see the house, and is now renting from us. However, the tenant agent now wants me, the land lord, to pay them a "finders fee."

I never had any agreement with this person the tenant hired. They came to my agent from the Zillow listing, so my question is do I even owe them anything? I expected to pay my agent, but not the tenant agent. 

Any insight is helpful, thank you!