There are a few ways to handle this scenario...
First, you could present a "Call Me Now" button. The user would enter their phone number they want to be called at, and you could submit a Callback request using the Genesys Cloud APIs. Genesys will call the user at that number ASAP. When you submit the callback request you can attach data to the call about the promotion presented or web page that they were on.
Second, you could use Genesys Predictive Engagement to send web browsing events to Genesys to track the user's web journey on your website. Then if they call into the phone number presented on the website, you can use the Journey APIs in the callflow to see if they were recently browsing the website on one of the pages where your campaign is running.
Third, we have some AppFoundry partners that offer click-to-call capabilities that use WebRTC so that the customer is calling directly from their browser and those calls can have data attached as they are started and therefore the callflow can utilize that data for routing.
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Jim Crespino
Senior Director, Developer Evangelism
Genesys
https://developer.genesys.com------------------------------