What is the ruling on calling upon the absent and the deceased to witness, as in the Hadith: "O Allah, I have awakened, calling upon You to witness, and calling upon the bearers of Your Throne, Your angels, and all of Your creation to witness..."?

The hadith does not mention making a distant person or a deceased person a witness. What is meant by "(I make) you and all your creation witness" is, as Al-Sindi said: "It is as if he intended by making them witness that he would not conceal his testimony of monotheism and prophethood from any of them. Even if it were possible for all of them to gather with him, he would bear witness to both matters before all of them. Thus, it became as if it were in the position of making them witness."