Object Auditing with Availability Groups
No, auditing only reflects the one server that is running the audits. If you want to centralize audit results from multiple servers, you'll need to combine that data yourself.

Keep in mind that if someone really wanted to circumvent this, they'd simply add another replica on any server they want, do the querying they need, and then destroy the replica. An audit on the primary would only capture the fact that a replica was added (and even then, only if you're auditing for those events.)