Cuban Doll Says She Doesn't Know Offset, Isn't To Blame For Split With Cardi B

Cuban Doll, the female rapper Offset allegedly tried to rope into a three-way with his supposed mistress, tells us she's definitely not at fault for his breakup with Cardi B.

We got Cuban out Thursday night at Topanga Mall ... and she's adamant she NEVER hooked up with Offset, and never even spoken to CB's hubby.

The denials don't end there, because Cuban tells us she had no idea Offset was trying to have sex with her and says she wasn't even aware of his alleged threesome fantasy before it went public.

As we reported ... Cuban was thrust into the middle of Cardi and Offset's split after alleged text messages surfaced appearing to show Offset looking to set up a menage a trois with Cuban and his supposed sidepiece, Summer Bunni.

We broke the story ... Summer tearfully expressed remorse for hooking up with Offset not long before Cardi gave birth, but there's no crying coming from Cuban.

And, get this ... Cuban says Cardi recently reached out to her, and there's no beef between them.