After installing the store app 'AWS Managed Services (AMS) Connector Application' there is an option to create 'AMS Accounts' which have a field 'Last Sync Time (Incident)'. This field is periodically updated. However, this may not update due to an issue with the feature.
The store app AWS Managed Services (AMS) Connector Application is not a ServiceNow app. The App is developed and supported by Amazon.
Please reach out to the Amazon using the contain information mentioned in the 'Support Contact' field of the App.