I don't think there's been any suggestion that Qantas is censoring the content produced - and if you are suggesting that, that's a big call to question someone's professional integrity.
You misunderstand the way corrupting forms of influence work. In particular, you misunderstand the difference between the quid pro quo and clientelist varieties.
Quid pro quo is where you give something of value in exchange for a particular favour in return (eg Qantas gives you a free business class ticket in return for a good review on a website).
No one has suggested that Qantas does this.
Clientelism is where you give something of value with no expectation of a particular favour in return (eg Qantas gives you a free business class ticket, but never says anything about what it expects in return).
The important point to note is that clientelism is just as corrupting as quid pro quo because clientelism creates a system of patronage. In other words, the person who receives the gift knows what is expected of them and thus they do not need to be told what to do in exchange for the gift. They know, in particular, that the gifts will stop if they write a bad review.
For example, AusBT knows that if they write a scathing review of Qantas' product, their source of inside knowledge about forthcoming announcements and future invites to product launches will dry up.
Qantas does not have to censor the content produced because they know the reviewer will self-censor.
If you'd like to learn more, the High Court of Australia talked about the distinction between the different types of corruption and the corrupting effects of clientelism in the political arena here:
McCloy v New South Wales [2015] HCA 34 (7 October 2015) (see paragraphs 36 to 38).