From the link that a non-Catholic, Grey Friar posted.
Fourteen years after Paul’s first visit to Jerusalem probably equates to AD 47. The Didache may be what Paul laid before the leaders in Jerusalem — a summary document prepared in advance for just that purpose — or more likely from the way it sounds, a set of lecture notes taken while Barnabas and Paul and Titus were speaking. In either case it is worth noting that in the Didache and in Acts 15:12 Barnabas speaks first. He was the leader at Antioch. Paul was his assistant.
when they perceived the grace that was given to me, James and Peter and John, who were reputed to be pillars, gave to me and Barnabas the right hand of fellowship, that we should go to the Gentiles and they to the circumcised. (Galatians 2:9)
The manufactured statements that your Didache puts in the mouth of Paul do not comport with his own words of the letters...read them carefully.