Policy to create a SubCategory and display that subcategory in the Visual Browse Window

I have to write a custom RAM policy which will do the following:-

User will create a SubCategory and that subCategory should be displayed on the left-hand visual browse window in RAM client.

It is understood that the subCatgory will not be displayed until it has a leaf node under it. But the requirement is that it should be displayed as soon as it is created (after the client refreshes).

When the user creates a "SubCategory Asset", I create the subCategory using the following API.
            matchedCategory= subCategory.createSubCategory(assetObj.getName());

and then I try to categorize assetObj which the "SubCategory Asset" that I just created, with the newly created subCategory.
categorize(assetObj,matchedCategory);

But this gives the following error.

Exception in thread "main" com.ibm.ram.common.data.exception.RAMRuntimeException: Subcategory Business Capability Catalog/Business Capabilities/Move Money & Process Payments/My Buss Cap Asset23 was not found for the asset My Buss Cap Asset23[1.0].
    at com.ibm.ram.client.RAMAsset.categorize(RAMAsset.java:2300)
    at com.cof.custom.policy.CustomPolicyUtility.categorize(CustomPolicyUtility.java:572)
    at com.cof.custom.policy.CustomPolicyUtility.createUpdateSubCategory(CustomPolicyUtility.java:538)
    at com.cof.custom.policy.CustomPolicyUtility.categorizeSubCategoryAssets(CustomPolicyUtility.java:495)
    at com.cof.custom.policy.CustomPolicyUtility.manageAssets(CustomPolicyUtility.java:426)
    at com.cof.custom.policy.CustomPolicyUtility.main(CustomPolicyUtility.java:882)

Will appreciate your help.

Thanks,

Sourav