Let me know if you end up researching this further and what the conclusion is. I think the best way to tackle this would be via an API the customers can give you.

The idea is a simple marketing tool to help businesses reach out to customers that didn’t convert fully through the funnel. So for example, user created a profile, but didn’t end up purchasing.

If interested, I can share the link (once it’s up) and would love to get your feedback.