Is it possible to prevent the source number from being applied to the promo code box in TNEW while utilizing source tracking from Wordfly links? Ideally, the tracking would be hidden.
We've done a couple of embedded promos for marketing tracking, and did a couple of things to keep it from drawing the eye:
1) We gave them really generic names in hopes they wouldn't draw the eye for the patron (similar to how you're using the numerical code instead of words)
2) We got rid of the "Promo Code" preface in Component Editor > Utility Navigation > Applied Promo Label. This is a global change but we have ours set so the Promo Code Placeholder Text is promo specific (ours says "enter promo") and the Applied Promo Label is blank.
Another idea would be some custom JavaScript that fires throgh google tag mangaer if a Source code equals a certain number. You could use the remove method to remove the promo box entirely if it is that source code number. You'd have to update tag manager everytime you have a "hidden" promo code.