Can Ebay app scan WhatsApp messages?

I've just my auction ended for allegedly attempting to sell outside of ebay. I messaged a mate (who is in the relevant trade) with a link to the product (not the ebay auction itself - I'm selling something I bought from a website and never used) and staying a price I'd be happy with and a couple of minutes later my auction was pulled. I didn't share any link to the auction which is baffling me.

Does anyone have any ideas what may have happened?