EDIT: You replied while I was typing. I'll leave my post below.
Believe me, the default "Shows" views in Standard and Theatre View works much better than what you are trying to do, I believe. I think you are making it hard for yourself.
If you have changed the Episode names so they sort the way you want, you will have broken the "Get Movie & TV Info" function I think, and that could be why you aren't getting Cover Art. But the "Get Movie & TV Info" function should still work if the [Series], [Season] and [Episode] tags are correct.
Which Cover Art aren't you able to find? Series, Season, or Episode? As I said earlier, the "Cover Art > Get from Internet" function will collect Series and Season Cover Art for you, while the "Get Movie & TV Info" function will get Episode Cover Art. It should be saved correctly if you run those functions, and displayed if your View is correctly built.
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Your first image shows that you are using a List Type of Thumbnails for the View you have shown. But it looks like you have built a View which just shows Episodes, and are not using the structured Series > Season > Episodes View layout. Also, it looks like the View is sorted by [Name], which for TV Shows is the Episode name.
You have been using MC for a long time, so I assume that you know how to change a List Type for a Standard View view, and that you know about Panes, and Detailed Panes. Unfortunately there is no up to date Wiki that explains the current View functionality, but there is some good information, and plenty in the forum.
Look at my first attached image. That is the default Video > Shows View, with just the Season and Episode columns added after the Episode name. It is sorted by Series, Season, Episode, with the top Pane just showing [Series], and the bottom Pane showing the default set of columns. The top Pane is using the Thumbnail List Type. The bottom details Pane is using the Details List Type. All the information you need is right there, visible.
My second attached image shows a modified View, with the way you want to see shows listed as a new first column in the Bottom Details Pane. See the column "Al ex's Column", which is shown as you describe. Not that I recommend showing TV Shows that way. But it is easy to do.
So, given that information, what are you really trying to do?
Use Standard or Theatre View?
Create a View that just shows a plain list of all Episodes in a Series, sorted by Series, Season, Episode, or just a flat list of ALL TV Shows, sorted the same way?