You mention the iwp_cron_runner hook which suggests you have the PRO version, can you make sure you have Import WP PRO 2.6.3 installed, and the latest Import WP version 2.7.6 installed, as these fix a few recent bugs with the scheduling, and also adds in a button to cancel the currently running import from the top of the edit importer screen.
Can you give this a try and let me know how you get on, since this is not related to the free Import WP, can you create a support ticket here: https://www.importwp.com/support/
The screenshot showing your import history, this is showing past imports (if your importer is currently running a notice should appear at the top of the edit importer screen, or below each importer on the importer archive screen.
Information about scheduling imports, configuring the WordPress cron and Importer scheduled notifications can be found here: https://www.importwp.com/docs/how-to-schedule-an-importer/
This ticket will now be closed, if you would like to respond please create a support ticket here: https://www.importwp.com/support/