Chapter 38 titled, 'Religion' in "Beelzebub's Tales to his Grandson" presents the possibility that Judas was the "devoted and favorite Apostle of Jesus" who left the Last Supper early in order to allow the other disciples to complete the "sacred sacrament Almznoshinoo". However, The Pesher of Christ, my major exposition, shows this to be untrue.
It is clear that, at least, symbolic bread and blood are being exchanged among the disciples in the verses: "Take, eat, this is my body;" (Matt 26:27), "This is my blood of the new covenant, which for many is being poured out; "(Mark 14:25) and "This is my body, that for you is being given, this do you -- to remembrance of me. In like manner, also, the cup after the supping, saying, "This cup is the new covenant in my blood, that for you is being poured forth." (Luke 22:19,20). In this ceremony Jesus was following the Essene practice as shown in by the Historians Philo and Josephus. Whether it was the "sacred sacrament Almznoshinoo" cannot be proven, but it can be shown that Jesus was taken off the cross still alive and therefore the disciples would have had no need for it.
Gurdjieff probably had read the gnostic Gospel of Judas which does support the concept that Judas was acting on the orders of Jesus to betray him and claims that he was the only disciple who had been taught the true Gospel. This shows the access that Gurdjieff had to ancient documents as the Gospel of Judas was not known in Gurdjieff's lifetime, having been rediscovered in 1970. It has not been accepted as true. The early Christian writer Irenaeus of Lyons, who, in arguing against Gnosticism, called the text a "fictitious history".
The decision to betray Jesus was not made at the moment to gain more time, but had been broached by Judas to Caiaphas, the Chief Priest, sometime between the end of December 32 AD when Caiaphas began plotting to kill Jesus and the actual day of the Last Supper in April 33 AD. Note that the symbolism of 'thirty pieces of silver' did not represent that Judas wanted money, but rather he was wanting to be given the position of levite, the second position (represented by silver) to the High Priest (gold). This was the same position (Man) that he suggested to Jesus in the forty days in the Wilderness with Jesus being third (Holy Spirit/ Son of Man). Jesus rejected this because he did not believe in opposing Rome as the Zealot Judas, the Sicarii dagger-man, did.
The symbolism of "thirty pieces of silver" comes from the organization of John the Baptist, inherited by Simon Magus, which was based on the moon cycle of 29 and one half days: 29 men and one female (worth half a man). (Silver representing the moon.) (See Triacontad)
At the Last Supper, Jesus did suspect that Judas would betray him, as he announced to the other disciples when giving him the piece of bread. This bread had been sopped in wine and may have also contained a drop of blood from Jesus' hand, not because of the sacrament Almznoshinoo, but to fulfill the concept from Isaiah 53:7 that he was the Lamb of God. On Passover a lamb would be sacrificed as it was before the Exodus of the Jews from Egypt.
Jesus' survival from the cross was not dependent on this ceremony because his survival is shown in Gospel Q Source beginning with Judas' betrayal by a kiss to the Placing of Jesus in a tomb and reviving him from the poison that made him appear to be dead.
It should not come as a surprise that almost all of the history in 'Beelzebub's Tales to his Grandson' was fabricated by Gurdjieff as an allegory. It was effective in achieving his goal: "to destroy, mercilessly, without any compromises whatsoever, in the mentation and feelings of the reader, the beliefs and views, by centuries rooted in him, about everything existing in the world." The "sacred Almznoshinoo" is also allegorical, being based on the concept of "blood brother". Please do not take this story at face value and cut each other's hands and share each other's blood before separate plane rides. Keep in mind that, if such a ceremony did exist, there is no record that Gurdjieff used it with his pupils. (You might make the claim that Gurdjieff felt that his students were not even advanced enough to have an Astral Body and therefore were incapable of bringing him back, but that cannot be true, because a Kesdjanian Body is not that hard to attain.) Gurdjieff places the concept of this ceremony here to attack people's belief that Jesus was resurrected as stated in the Nicene Creed and to show that Jesus was not God as the Christians believe. The Pesher of Christ has accomplished this now.
Whether or not we can communicate with a the Spirit (Kesdjanian Body) of one who has passed away may well be possible, even without the ceremony of Almznoshinoo, not because gravity acts on matter (a silly idea since Spirit is not matter that is subject to gravity), but rather because Spirit has an affinity with Spirit. After all, the clouds, on which the angels metaphorically live, often visit the earth like the fog that lives in high mountains. (See my experience at Gurdjieff's Grave.)