1996 Honda Accord Catalytic Converter Deficiency

When my check engine light came on I had it checked and the error message was Catalytic Converter Deficiency. I had the catalytic replaced by a local shop that welded on a new catalytic instead of using a after market factory bolt on like Honda uses. A week later the check engine light came on again with the same error message "Catalytic Converter Deficiency". Another shop told me that because the other shop didn't use the proper catalytic for my Honda that I will continue to get a check engine light until I replace the catalytic again with the correct catalytic. Is this correct??