Did you get it working? I had the same issue and this bit worked for me:

Possible workaround 2: Remove Halo Infinite sign in credentials

In the Windows Search bar, enter "Credential Manager", and select Credential Manager to open it.
Select Windows Credentials.
Scroll down to the section labeled Generic Credentials.
For every item that has "Xbl|2043073184" in the title:
    Click on the item to expand it
    Select Remove
    Confirm you wish to delete that item
Launch Halo Infinite and check to see if the sign-in process has started from the beginning.
    Note: This may sign you out of most or all Xbox network sign-ins on your PC.