Something that I started using and so far they have believed it,,,,
I will ask for the target. When they get on the phone, I will go right into asking about apartment availability, just as if she had initially answered the phone. First of all, they aren't always going to ask how you got their name or why you asked for them. Then, you are good to go, don't bring it up.
If she asks, I will tell her that my asst was helping me with my apartment search by making initial calls to see what was available. She must have spoken to you then because she gave me your name as the person to contact. And I just really don't make a big deal about it, act like Hmm, I don't know why she gave me your name. Maybe you answered the phone when she called last week to check your hours.