Being able to dynamically set a cookie value based on an element's value seems like a no-brainer as you can inject it into s.products but I see no documentation and my attempts have failed.
Example of what seems overly simplistic, but at least to me, should work; _satellite.setCookie('source','ELEMENT VALUE',1);
Have a look at https://marketing.adobe.com/resources/help/en_US/sc/implement/util_cookiewrite.html
If you are running AppMeasurement.js you can use that build-in function to write your cookies...
/LøjmannCM EDIT: Added hyperlink to text
_satellite.setCookie('source','ELEMENT VALUE',1) should work fine
When you use
What is happening? Have you used
_satellite.getVar('DATA ELEMENT NAME');
to verify that the data element you are trying to use to set the cookie has a value?