Liam Payne's pal Roger Nores is still wrapping his head around being cleared of manslaughter charges tied to the singer's tragic drug-fueled death -- and the main thing he wants now is an apology from Liam’s dad, Geoff.

Roger appeared on "TMZ Live" Thursday, explaining that even though Liam’s dad is the reason he faced charges, he’s holding no grudges -- BUT for that defamation lawsuit to go away, Geoff needs to show some real remorse.

Roger tries to understand Geoff's actions, acknowledging to us that there's no greater loss than losing a child ... and how that feeling of responsibility could drive someone to blame others, even when they don’t have all the facts.

Watch the whole interview ... Roger shares his attempts to reach out to Geoff, emphasizing he's not seeking money -- just trying to tie up loose ends so he can finally put this chapter behind him.

He also discusses the grief he's been carrying, admitting that amid the legal chaos, he never fully processed Liam's death. But now that the charges against him have been dropped, he’s finally ready to confront the loss.