I updated this to show a single gift card at $50 with no AUD specified, and resubmitted.
I'm now being informed that Gift cards in itself is not allowed as per the Merchant Policies. The Gift card which you are selling is not a tangible product.
My question is, surely there must be a way to offer this Shopify feature whilst also having the benefit of leveraging Google's Shopping channels? And if not, should there be clearer information upfront, from Shopify, about the inability to use gift cards in conjunction with Google Merchant Center?
Any help or thoughts on this would be great! Thanks