Kliska, no matter where the apostles went, no matter where you find the early Christian Churches, you find consistently without exception, a belief in the Real Presence. It is with this understanding the John 6 needs to be read. You do understand that the biblical canon was put together in part to have a universal set of readings for the Catholic Mass?
We can read the writings of this early One Holy Catholic and Apostolic Church. St Ignatius was a disciple of St. John the Apostle. Justin Martyr says that they have been taught in this apostolic faith.
“They abstain from the Eucharist and from prayer, because they confess not the Eucharist to be the flesh of our Saviour Jesus Christ, which suffered for our sins, and which the Father, of His goodness, raised up again.” Ignatius of Antioch, Epistle to Smyrnaeans, 7,1 (c. A.D. 110).
“For not as common bread and common drink do we receive these; but in like manner as Jesus Christ our Saviour, having been made flesh and blood for our salvation, ***so likewise have we been taught ***that the food which is blessed by the prayer of His word, and from which our blood and flesh by transmutation are nourished, is the flesh and blood of that Jesus who was made flesh.” Justin Martyr, First Apology, 66 (c. A.D. 110-165).
PnP