Answer
Identify the target Quick Report and target Window first, then navigate to 'New Custom Menu.' Fill in the details, including selecting the target Window the RMB should appear on; choose the action type as Quick Report specifically; select the actual Quick Report to link to; optionally adjust where in the menu the new item appears; add any needed translations; and save. If the new RMB option doesn't immediately appear on the target screen, RMB on that screen and choose 'Reload Configuration' to refresh it into view.