Corinne sat down with Chris Harrison on Tuesday's 'BiP' tell-all episode and confirmed TMZ's story -- she mixed meds with booze and suffered a hard blackout when she hooked up with DeMario.

Chris also confirmed our reporting about Corinne appearing very with it during the ordeal that eventually shut down production-- so much so producers thought she was fine.

The bigger takeaway ... Corinne officially exonerated DeMario of any wrongdoing and said there's no ill will on her end. She also said she never blamed him for anything.