Are you 100% sure that when sending data from the "Bob" file, the filter displays exactly the same records in the "Ham Sandwich" file as in the "Bob" file? If the answer is "No", then both files should use a unique record identifier, e.g. an ordinal number in the "Ham Sandwich" file.
Regardless of the solution, when data is returned from "Bob" to "Ham Sandwich", the data should be moved record by record.

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