The tape can be found inside the Burrows, on a metal shelf near a riverway of lights.
Trish: Dylan, I hope you find this when you get back. I need you to listen to me. We can't stay here anymore. Marcus, that son of a bitch. I should've known he'd... *sigh*. The point is, you need to grab your things and leave as soon as possible. Just don't try to leave through the central chamber. One of his goons will just hold you up and give you shit. I'm heading to Mosstown now. I love you and... I hope I see you soon.