I'm assuming you turned on the option: "Purchase Order" in your pay path's tab summary & payment.....
If yes, "Purchase Order" should show-up as a payment, under data tag: {[C-PAYMENT METHOD]}.
Then creating a data tag for the registrants entry is the cleanest way to make it happen on the invoice. Create a data tag for the custom field. Add both data tags to your invoice via the badges and certificates function.
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Jacqueline C. Ward, CMP
Director, Continuing Legal Education & Special Events, UNC-Chapel Hill
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