TestCafe can't establish browser connection when running against Electron app - testing

Question

I am attempting to run a test on our Electron app using TestCafe. I have tried many things but after many hours am still getting the error below:
"ERROR Unable to establish one or more of the specified browser
connections. This can be caused by network issues or remote device
failure."
The cases I have read Googling around do not seem to apply to my case.
I have everything set up as described here: https://github.com/DevExpress/testcafe-browser-provider-electron#testing-an-executable-electron-application
The .testcafe-electron-rc file is correct in that my app does indeed launch but errors as above. I do not think it gets to my script which is very simple for debugging purposes. I have tried changing the mainWindowUrlPath to various locations since it seems like my app is run from C:/Program Files/MyApp/resources/" which contains an app.asar file even though our app is located in "C:/Program Files/MyApp/MyApp.exe"
I have tried setting up the .testcafe-electron-rc in many configurations including the one described in the documentation as well as many others. An example is below which I realize is non-standard:
{
"mainWindowUrl": "C:/Program Files/MyApp/resources/app.asar/index.html",
"electronPath": "C:/Program Files/MyApp/MyApp.exe"
}
Note, I have never seen the index.html anywhere in the app directory but assume that TestCafe must dive into the asar in some manner.
I have disabled the Windows firewall but still, the same issue exists.
I have run my tests with nodejs installed globally and testcafe and the Electron provider installed globally and locally (i.e. run these configurations separately) but the same issue occurs.
Does anyone have any other ideas? Any help appreciated.
This is on Windows 10.
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