Who actually holds the mortgage on planet earth?

Satan actually holds the mortgage on planet earth. According to Revelation 5, the sealed scroll is that mortgage. Satan picked it up when Adam fell and lost his dominion, and he has been the god of this world ever since. Though God holds the scroll ready to be paid off, Satan remains the real holder.

Les teaches that the scroll in Revelation 5:1, sealed with seven seals, represents the mortgage on planet earth. He explains that Satan acquired this mortgage when Adam fell and lost his dominion, and since then Satan has been the god of this world. Les cites the statement that the world lies in the lap of the wicked one, and another that Jesus Himself said, that he is the god of this world. God the Father holds the scroll, ready for it to be paid off, but Satan is the real holder and has the mortgage on the planet.

Revelation 5:1

And I saw in the right hand of him that sat on the throne a book written within and on the backside, sealed with seven seals.

If God holds the scroll in Revelation 5, is Satan still the real holder of the world's mortgage?

Yes, although God the Father holds the sealed scroll in Revelation 5, the scroll represents the mortgage on planet Earth, and Satan is still its real holder. He acquired it when Adam fell and lost dominion, and he has acted as the god of this world since then.