Nobody approves it because you already did.
The Standard Terms and Conditions attached to your vendor agreement give Walmart the right to deduct against what it owes you, and to audit backward against documentation you may no longer keep.
Most suppliers sign that before the first purchase order and never read past pricing and payment terms.
Once you can see what the agreement authorizes, SQEP, OTIF, and post-audit stop looking like three separate compliance programs. They start looking like three ways of enforcing the same language.