Discount (Sign Up) Popup when Customer leaves Cart

I have tested this popup, and it works, but…….

Issue is the list “confirmation email” needs to be different for this specific Sign Up Form. 

Two unique list email confirmation is not a thing from what I can tell.

What I Want:

1. Customer adds to their cart
2. Views cart
3. Navigates away from cart and this triggers the popup that says “want a discount right now?”  email field.  Where should I send coupon? button says “send me my coupon”.  (list is double Opt in)
4. Confirmation Email subject is “Here is your coupon”.  Email has the coupon as promised and underneath is a an offer to Subscribe to the newsletter and reasons why etc.  If you are interested, hit subscribe, if you are not, enjoy the coupon and delete this email etc.   Button says subscribe.  
5. They buy with a discount. Popup converted!
6. If they subscribe it is a bonus.  It also means they did not subscribe for the discount and will not unsubscribe the very next email.
7. If they do not click Subscribe button and delete the email,  they are actually not confirming their subscription and we both win.   I have not added them to a list they did not consent to be on.  Seems devious I know, but I do not know how else to accomplish this.

I could create another list, but that creates soooooooooo much more work with flows etc etc.

I am not with Shopify.