From a quick search it looks like they support REST API, Concur Developer Portal | REST API Basics, so the Qlik REST Connector can be an option. The data source provider will be the best source (if not only) to help you find the connection details needed to configure the Qlik REST Connector. Please review the Qlik Connectors documentation for the Connector version you are planning to use, and align the settings with details from Concur.