select one of these files and check which tag versions you have in it: just ID3Vx or also APE tags?
You can see that in the window title of the extended tags dialogue or a column fairly far to the right.
The check which tag versions you read, write and delete: see
File>Options>Tags>Mpeg.
If you do not read or write APE tags but they are still in the files, it could be that you see the contents of the APE tags in the other programs.
To remove the APE tags, select "Delete" only for APE tags, do not tick V2 or V1.
Then use the function from the context menu of the files list: "Cut tag".
The APE tags should be gone now.
Now check in Windows explorer if you see the correct album artist.