Alright. So I reset the artwork cache and updated to the latest version. Still having the same problem. However I did discover some very odd things after messing around with it all day in an attempt to fix it.
First thing I tried was deleting a few of the albums I'm having trouble with. After deleting them I redownloaded and/or reburned them and added them back into my library. Same problem. No fix. Tried tagging them through MB, MusicBrainz, manually, etc.
So I downloaded Media Monkey and Winamp. I loaded my entire library onto both and have zero problems with Cover Art showing. And like I said earlier I had zero problems with Musicbee until I updated to 3.0 and higher.
Next step was downloading a separate mp3 tagger (always used MusicBrainz but tried something else) and erased any pictures embedded into a few of the albums that I was having trouble with. I loaded MB back up, re-scanned everything, and used MB to select a picture by either the "Search the Internet for a Picture" option or the "Auto-Tag by Track" button and the "Update Missing Artwork". And it worked. Kind of.
So if I click on the "Album Artist" and the Album that appears near the top (meaning its one of the first visible ones on the list) the Cover Art will now show. However, If I have to scroll down the Cover Art won't show (meaning I tried the above fix but it won't work). However, when I scroll back up, the Cover Art that originally showed now disappears. I included a few pictures as an example if I didn't explain that correctly...
Example #1-Clicked on Eddie Money. Can't Hold Back Album now showing Cover Art-
https://postimg.org/image/pphso2qq3/Example#2-Scrolled down. Another album I was having trouble with-Cover Art not showing even after doing above fixes-
https://postimg.org/image/5pmdufv87/Example #3-Scrolled back up to original Eddie Money-Can't Hold Back Album-Now Cover Art is gone-
https://postimg.org/image/7yy8r7xmj/So yeah. I don't really know what to make of that. I hope it helps.