Why was Paul bombarded with accusations meant for false teachers?

Paul was accused of not bringing the truth because he refused to agree with the Judaizers in Jerusalem and no longer worked hand in glove with Peter and the eleven. Since he proclaimed something they knew nothing of, false accusations that belonged to false teachers were aimed at him instead.

Les explains that Paul did not come with fickle language; everything he said was prompted by the Holy Spirit, and he was there for the love of Christ. The love of Christ constrained him, enabling him to suffer the privations he later lists in II Corinthians. In verse 17, Paul was being accused of not bringing the truth because he was not agreeing with the Judaizers in Jerusalem and was not working hand in glove with Peter and the eleven anymore. He was proclaiming something they really knew nothing of, so he was bombarded with false accusations that should have been reserved for false teachers. Les points out that it is so often the other way around: instead of false teachers being bombarded, those with the truth come under attack.

Why was Paul hit with accusations that should have been aimed at false teachers?

Paul was accused because he did not agree with the Judaizers in Jerusalem, no longer worked with Peter and the eleven, and proclaimed something they knew nothing of. These false accusations should have been reserved for false teachers, but instead those with the truth often come under attack.