Initiates server-to-server (S2S) KYC verification for a customer who has already uploaded the required documents using the /v1/customers/kyc/upload-document endpoint.

This is step 2 of the S2S verification process. Before calling this endpoint, upload all required documents.

For business customers, complete KYC verification for every associated person before starting the business's verification.

On success, verification is initiated and the review outcome is delivered later by webhook. Business customers must upload a registration certificate first, or the request fails with a 400.