Link tracking issue - once the Buy button is clicked, we cant track the user for our referral partners

Our company websites run through Webflow and the embed shop product pages are made in Shopify. We also use Infusionsoft to track everything because we are a wholesaler. For some reason once the user clicks on the buy or add to cart links from Shopify we are no longer able to track the customer. I don’t want our referral partners to miss out on commission. The referral link is pointing to the company domain and the shopping cart is sitting on another domain ( is making tracking the partner not possible (even custom developers have not been able to pass the affiliate ID through to the popup window because of the restrictions around the Shopify buy buttons). Does anyone know what is going on here and why it is so complicated to resolve?