by thumper that day, he said they'd taken heidi in the van to the home of a young woman named jennifer wescotthe screamed, if you don't believe me, go ask jennifer. >> what we wanted to do is try to follow up to see if there was any truth to that. >> reporter: jennifer wescott was a girl tonya knew from high school. the d.a. encouraged her to get in touch by facebook. they exchanged telephone numbers, and then it was time for a phone call. >> they plugged into my phone, taped the whole conversation. hope she'll answer. [ ringing ] >> hello? >> reporter: it had been years since they last spoke. tonya made small talk at first. and then eased into the story she'd heard, the murder of heidi all those years ago. >> he just told me that they grabbed her from the store and they brought her to your house. >> i really in my own head dropped that. >> right. >> i don't know, probably about ten years ago. >> reporter: jennifer didn't deny a thing, but she wasn't saying much either. >> why did they even involve you or even do this? >> i don't know. >> you don't know which one killed her, though? >> no idea