I am assuming you are using loop back connector to promote works groups as entitlement. If you want newly created workgroup in API without aggregation then you need to create the entitlement also as part of workgroup creation process.
here’s the sample code to create workgroup as entitlement
import sailpoint.object.ManagedAttribute;
import sailpoint.object.Identity;
import sailpoint.object.Application;
ManagedAttribute managedAttribute = new ManagedAttribute();
managedAttribute.setValue("<name of the workgroup>");
managedAttribute.setDisplayName("<disaplay name of the workgroup>");
managedAttribute.setOwner(context.getObjectByName(Identity.class,"<owner of workgroup>"));
managedAttribute.addDescription("testing wg as entitlement","en_US");
managedAttribute.setAttribute("workgroups.name");
managedAttribute.setApplication(context.getObjectByName(Application.class,"<loopback connector application name>"));
managedAttribute.setType("workgroup") ;
managedAttribute.setRequestable(true);//true or false depending on the requirement
context.saveObject(managedAttribute);
context.commitTransaction();
Can you elaborate a bit on your use-case, as I fail to understand the combination of the SCIM API call to IIQ to something which is not yet in IIQ. And later perform the aggregation the workgroups.
Also which workgroups are you referring to:
Active Directory Workgroups (as entitlements in IIQ)
IIQ Workgroups (groups of identities which are groups and can be used as an owner of for instance entitlements, roles, apps or used to define additional permissions)
To better provide an answer some more context is needed.