I had a similar problem and posted a similiar question on this forum but was able to work through the issue and answer it.
If you search on "staging table update stored proc not working" in this forum you will see the thread I created.
Essentially if you are using the stored proc to update the stg tables then use BATCH_ID, BATCH_TAG is used when you update from the MDS Internet app.
I commented out the "RETURN_VALUE" code as per below:
---DECLARE @return_value int
EXEC comment out the @return_value param = [stg].[udp_CATEGORIES_Leaf]
@VersionName = N'VERSION_1',
@LogFlag = 1,
@Batch_ID = 1
---SELECT 'Return Value' = @return_value
I recall the stored proc also asks for the update type which you don't see here - refer to the MDS documentation on the Microsoft site but I think 0 is the best value to use intiailly.
Check the current Batch_id in your table via the MDS schema in SQL Server and ensure you have the correct Batch_ID in your stored proc.