the Bible never puts peter in rome, his calling was to preach to the jews, paul’s was to the gentiles and we know paul was in rome:
Romans 15:20 and thus I make it my ambition to preach the gospel, not where Christ has already been named, lest I build on someone else’s foundation
(Hope no one minds if I pop in…)
So… if Peter was only called to preach to the Jews, then Paul was wrong to rebuke him at Antioch…
Galatians 2:11-12
11 When Peter came to Antioch, I opposed him to his face, because he was clearly in the wrong.
12 Before certain men came from James, he used to eat with the Gentiles. But when they arrived, he began to draw back and separate himself from the Gentiles because he was afraid of those who belonged to the circumcision group.
So, evidently, since Peter was called to preach to the Jews, he was stepping out of his bounds by ministering to the Gentiles.
In other words, your proposition that Peter was called to minister exclusively to the Jews, Paul exclusively to the Gentiles is totally nonsensical, especially considering the Great Commission:
Matthew 28:16-20
16Then the eleven disciples went to Galilee, to the mountain where Jesus had told them to go.
17When they saw him, they worshiped him; but some doubted.
18Then Jesus came to them and said, “All authority in heaven and on earth has been given to me.
19Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit,
20and teaching them to obey everything I have commanded you. And surely I am with you always, to the very end of the age.”
ALL nations. Not just the Jews. And we know Peter was there, unless by “eleven disciples” Matthew means, “every disciple except Peter, including the corpse of Judas Iscariot.”
And all else aside, there was in fact a Jewish population in the city of Rome. According to the oh-so-dependable Wikipedia, at the time Caesar Augustus began his reign, there were over 7,000 Jews in the city of Rome (
en.wikipedia.org/wiki/Jewish_diaspora). So, it would not be so far-fetched anyway for Peter to go to Rome to minister to the Jews.
As for Romans 15:20, the epistle to the Romans was written in 57 or 58 A.D. Peter died in Rome sometime in the 60s A.D. What tells you that Peter could not have gone there later than when Paul wrote his letter?