[MaeWest]

Maybe she was on her way out and remembered it sitting in the dryer in the laundry room, but was running late so ran to get and just threw it by the door inside the apartment

Yes. If she got "the call" to meet in the park she would have been in a rush. Or she could have been taking a blanket with her for the tryst - she could have decided to take a different one and threw that one down before grabbing another and rushing out the door. How big/bulky was this blanket on the floor?

[hoosiermama]

Wonder if there was a phone near the laundry room and if it were checked for calls?