Odin "stops working" when I try to use the re-tarred AP file as .tar.tar or .tar and won't load it if I change it to tar.md5 (md5 error! Binary is invalid). That AP file loads way too quickly anyway, the AP load usually makes Odin go to "not responding" for a couple minutes.I do them on Linux, but they can also work on WinBlows. Since I do not use M$ products, I can only say I've seen those commands work on WinBlows, but can't say how to set that up.
I also can't help you with 7zip, it can run on Linux, but never use it myself.
People have problems when they don't use "real" tar, so don't. Save yourself the pain.
You do not need to convert the .tar to a .tar.md5. Odin will use either file type. A .tar.md5 file is a .tar file with its md5 hash appended. Odin can use the file to verify the .tar integrity, but that is optional.
I'll see if I can make your process work on Windows.
Man I hate Samsung more today than yesterday.
ETA: I tried making the .tar with WinZip instead of 7zip. It kept a WinZip icon on the file and seemed to go through the Odin process too quickly, but now ADB is actually showing more apps instead of just .com stuff.
Still not actually rooted.