We are trying to use the whitelistParentDomain concept for one implementation. The case is that domain A is not controlled by us and it is also missing the Visitor Service ID (they use an old version H.27.2). In addition the page includes domain B (our domain) using an iFrame. According to the documentation (whitelistParentDomain and whitelistIframeDomains ) this falls under Use Case 2.
Despite we are able to create the Visitor Service instance and get the Marketing Cloud VisitorID (using getMarketingCloudVisitorID method) the AMCV cookie is never created under the domain B. So we are not able to create a persistent VisitorID for other subdomains in domain B.
Should we apply a different configuration than the one at Use Case 2 example?