Yes, it sounds like quite a convoluted ownership path. Whether they are “obliged” to fix it is questionable - I guess there is no way to force them so you are really just relying on the helpfulness of the current devs.
It would certainly be worth asking! Very helpful community here. If you wanted to discuss your mySql query on a Slack channel you’d probably get some advice.
Now if you uninstalled and deleted the plugin after making that transition over to CP, would you simply install a latest version of the plugin? And if yes, could you please send the URL for it again (I think it was at at Git but I don’t have it bookmarked).
A minute or two and it should be operatonal as normal but with latest WP version.
As of 08/24/2019 this will be 5.2.2. Gutenberg looks essentially unchanged since a few months ago.
Divi settings will back to be adjusted.
Go to Divi Theme Options.
Then go to Builder, Advanced, switch off CSS, switch on Enable Classic Editor and Enable The Latest Divi Builder Experience.
Then tweak it to use the wire-frame builder version.
This is very similar to back-end builder but much faster and STILL permits going back and forth between Visual Builder and wire-frame builder, or you can use the Visual Builder if desired. Whenever working with text or the WP editor it will look as before with the Classic Editor and be usable.
Next go to WordFence and change settings. WordFence scan will still show some CP images as security issues. They can be deleted or marked as fixed.