He could have googled you and found you on a profile without loggin into social media. It’s possobel , I’ve done it .
Just my two cents ...
Also if you knew this , you could have asked her to clarify to, and tell her . She would make likely clarify or say she wasn’t connecting ...
I’m not defending her ( her stuff hasn’t come to pass for me yet ) but I’m just saying there could be a reason why she picked that up