Seems that "audit-proof" is even more commonly used than "audit-compliant".

See examples:

http://www.intelligentmedicalrecords.com/benefits.htm
"IMR provides ***audit proof*** documentation"

http://www.dispositionsolutions.com/DS_LearningCenter_Myths....
"Reality: Our thorough documentation of the process is well-honed and ***audit-proof***.
Disposition Solutions Inc. has extensive experience in generating ***audit-proof documentation*** of the asset distribution process. If necessary, we can provide access to accounting professionals with expertise in asset distribution to further smooth the accounting documentation process."

http://www.proactivetaxsolutions.com/sb_services.html
"What can I do to take more of my bottom line home??

Actually small business owners' are the best candidates for tax planning strategies. The tax courts have held that there is nothing illegal or sinister in a tax payer arranging one's affairs so as to pay the lowest tax legally available. PATS tax saving strategies are tested and proven to prevail under audit. ***Audit proof documentation*** and a good business reason for the expense is the proactive stance for using the full breadth of the tax court decisions."