Unable to uninstall SDK preview versions

I have 2 SDKs installed:

1. `Microsoft .NET Core SDK 3.1.300 - preview (x64) from Visual Studio`
2. `Microsoft .NET Core SDK 5.0.200-preview.20614.14 (x64) from Visual Studio`

If I try to uninstall them using `Add or Remove Programs`

I get the following errors:

I have uninstalled the Visual Studio installations which originally installed these SDKs so I'm not able to run the Visual Studio Installer to modify and remove them.

**N.B.** I would have expected that when I uninstalled the Visual Studio installations which originally installed these SDKs that the SDKs be removed at the same time rather than being orphaned.

I have tried using the `dotnet-core-uninstall` tool but these SDKs are not listed when running the command:
`dotnet-core-uninstall list --sdk --x64`

The only way I can see that I can remove these SDKs is to re-install the Visual Studio installations that originally installed them to see if I can repair/modify the installations so that I can uninstall the SDKs prior to uninstalling the entire Visual Studio installations again. Unfortunately I don't know which versions of Visual Studio installed these SDKs and even if I did I don't think the old Visual Studio Community Preview versions are still available to download and install.