Hi MAJackie,
Thank you for your post.
The Pay Super function does require a TFN for contributions to be processed, however, in your case you may be able to substitute the TFN with one of the numbers listed on the ATO's Section A: Payee details page.
If you were still unsure, I would recommend speaking with the ATO on what TFN should be used, or if you could possibly use the ATO Clearing house to submit that payment.
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