If the file is deleted, it means that there is another component than HTML Viewer that deletes it, and therefore should also be kept
And yes, you can
You can already test by recovering the file in an full ISO/image and copying it to the System32 directory.
This will give you an idea of whether you need the component (with the registry keys) or if just the .exe file is necessary.
EDIT: sometimes the associated .mui file is also necessary