Oda didn't debunk anything, he says he follow orders but not kind of that he would do ''everything'', Zolo or Nami is not listening everything Luffy says as well.
Oda literally says Aokiji joined BB Pirates to be live ''freely'', so you need to read better.
Aokiji joined BB to live freely.
Meanwhile WB says he isn't a follower of Xebec, so the difference is clear.
Same way Law go to Wano with Luffy?