Hi ,
This type of issue occurs when you had a previous version of Datasmith installed, in this case the 5.0.3 version, and not all files were removed when it was uninstalled.
To fix it, you need to download the 5.0.3 version of the plugin from https://unrealstudio.epicgames.com/UnrealDatasmithSketchUpExporter_5_0_3.msi and install it, which should complete as normal. Once installed, uninstall it using the Windows uninstaller, which should remove all files. After this, the newer versions of Datasmith should install successfully.
Best,
Raghib