I would say the "Z" has a firm grasp of what is needed.
Public display that satisfies the skeptic's needs of evidence. For me it might be the creation of another planet just like earth, and a flight to it . . .
An Omniscient Deity would know EXACTLY what each person's needs would be in this regard . . . And belief in God doesn't necessarily mean that He/She would have a devoted follower worshiping Him/Her.
The Abrahamic God could prove Himself, but then if He did those actions recorded in the Bible why would anyone worship Him? . . . Out of fear of Wrath? . . . Sign me up, I would be the first to martyr myself AGAINST following a God like that.
I would believe in them, but I wouldn't bow down to them.
Also, you will find EVERY Atheist is open to evidence and proof of anything Supernatural. We are the most open minded individuals you will find.