AWS Marketplace: is there a way to track which customer has paid for Pay-as-you-go subscription and which not?

You can try using AWS marketplace Data feed for getting the invoiced report and pending disbursement reports.

https://docs.aws.amazon.com/marketplace/latest/userguide/data-feed-billing-event.html#data-feed-example-query-pending-disbursement

Hi Alena, check out the seller dashboards! In particular, the Collections and Disbursement dashboard shows you the disbursement status of each invoice that has been issued to your customer, the due dates of these invoices, and amounts, etc. You can take a look at Section 6 in the relevant guide: https://docs.aws.amazon.com/marketplace/latest/userguide/collections-disbursement-dashboard.html#section-6-granular-data