How do I migrate some older .NET Framework apps to GitHub?

18 months ago, we migrated hundreds of TFS/TFVC repos from an old, on-premises TFS server, to our GitHub Enterprise organization. There are, however, two TFVC repos still in that old TFS server because they are written using .NET Framework 4.5.2 and TFS seems to handle deploying those better than GitHub Actions does. They are WPF apps. We do have a GitHub Self-Hosted Runner, which I could use, but I've never been able to get it to create a ClickOnce deployment, and I've spent over a year trying to find a way to do that, with no success.

Well, we would like to get rid of that old TFS server. But before we can turn it off, I've got to find a way to make a deployment of some sort to the network shares for those two ClickOnce WPF apps. I see the .NET Framework 4.5.2 being an issue. (I tried, unsuccessful, to get the developer to upgrade to a newer, supported .NET Framework, but he refused.) And I don't even think GitHub Runners support ClickOnce deployments, regardless of if they run on GitHub or self-hosted runners.

So, what approaches would you recommend to me, please?