Does Client having Finance Module License allowed to use HDL

Summary: My Client is having only License for Finance Module and for HR they using 3rd party system. However they need to create employee record in Oracle Cloud and for that they using webservices and HDL Integration cababilities to create the same. To do that client is attaching Human Capital Integration Specialist Role to the admin user account which is used for Integration capabilities. Does my client can use this Role without having HCM License. They dont want to buy the HCM Licenses and in that case what will be the alternatives for Integration to work

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