NYC broker agreement says commission is due when landlord accepts my offer. Is this normal verbiage?

moving to NYC and considering working with a rental broker. We agreed to a fee equal to one month’s rent if I lease an apartment they introduces me to. My concern is the payment clause. It says the commission is “due and payable upon acceptance by the Landlord of the Renter’s offer.” I’m worried that could mean a fee is due even if the lease is never signed. Am I overthinking? For people who’ve rented in NYC, Is a landlord-acceptance payment trigger common? Is there anything else in this arrangement I should scrutinizeed before signing? I reached out to a family friend who is a lawyer, waiting for them to get back to me.