Acts chapter 2
41Those who believed what Peter said were baptized and added to the church—about three thousand in all. 42They joined with the other believers and devoted themselves to the apostles’ teaching and fellowship, sharing in the Lord’s Supper and in prayer. 43A deep sense of awe came over them all, and the apostles performed many miraculous signs and wonders. 44And all the believers met together constantly and shared everything they had. 45They sold their possessions and shared the proceeds with those in need. 46They worshiped together at the Temple each day, met in homes for the Lord’s Supper, and shared their meals with great joy and generosity—47all the while praising God and enjoying the goodwill of all the people. And each day the Lord added to their group those who were being saved.
So where did the others who were there that did not believe them go? Likely home. Keep in mind they came too observe a Jewish tradition and not too hear what they heard.
There is nothing incompatible with these initial converts going home shortly afterwards and the church being forces out of Jerusalem a couple of years later into the surrounding nations.
Yes there is but you just want to argue about it. One thiong is staying in communication. It wasn't like hey let's call Brother Peter. Where people went too they walked. Time, Distance, and Communications meant everything. Do you ignore chapter 6 and the problems which were beginning to happen within the believers community? It shows Jews from different nations still there even as far away as Greece. The Bible shows us this was a fast growing community. On to Chapter 8 what does it say about Stephens death?
A great wave of persecution began that day, sweeping over the church in Jerusalem, and all the believers except the apostles fled into Judea and Samaria. 2(Some godly men came and buried Stephen with loud weeping.) 3Saul was going everywhere to devastate the church. He went from house to house, dragging out both men and women to throw them into jail.
4But the believers who had fled Jerusalem went everywhere preaching the Good News about Jesus. 5Philip, for example, went to the city of Samaria and told the people there about the Messiah. 6Crowds listened intently to what he had to say because of the miracles he did. 7Many evil spirits were cast out, screaming as they left their victims. And many who had been paralyzed or lame were healed. 8So there was great joy in that city.
It shows Jews from different nations still there even as far away as Greece.
LOL, you forget that the Greeks maintained an extended period of control on Israel. Many had returned ancestral homeland after the diaspora who's primary language was Greek. Fact is that these Hellenists and Hebraists had their own separate synagogues in Jerusalem long before the start of the church. Hint - this was long, long before the beginning of the church.
But you are trying to suggest what the bible did NOT say: where they were FROM.