Ran into this issue today.  Dell is only posting WDM 5.7.3 to the Dell Digital Locker for customers with active support maintenance. At this time it will not be made available to the FTP site as customers are being migrated to WMS. I requested that this should be added to the FTP site for customers using the free (workplace) edition as WMS is still buggy.
Hello, Does anyone have a copy of WDM 5.7.3? Seems like Dell isn't posting it on the FTP site for download.
Dell Wyse Device Manager 5.7.3