Galatians 2:9 as counterexample to Keener's first argument

In Galatians 2:9, Paul says James, Cephas, and John 'perceived the grace given to me' and gave the right hand of fellowship. Paul was called by God and didn't need their affirmation personally, but appeals to these apostles for the Galatians' sake as external confirmation. This is a more nuanced reading of Paul in Galatians 2 than the common view that Paul disregards the apostles.