Multiple decoding blocks on SAMLResponse

I have an ASM policy that is blocking a POST with a SAMLResponse token due to a Multiple Decoding violation. I have the passes set to 3, but the SAMLResponse token has many instances that are viewed by the ASM as Multiple Decoding.

Is there a way to "tune" the policy for this without turning of the entire Multiple Decoding feature? I have tried creating a File Upload Parameter with Base64 Encoding enabled as well as a Parameter with Ignore Value as the Parameter Value Type. Neither of these options have worked.