Something seems off here. You have a lot going on in your Child theme’s functions.php, but nothing that seems like it should cause any errors.
When you said this:
I tried to put the “akita” folder per FTP on my webspace. That didn’t work proper, got some error about one folder couldn’t be placed within the framework folder. So I deleted the whole “akita” folder on my webspace and gave it another try – it worked. At least it seemed so.
I also have an updated of the old akita folder on my webspace.
… It kind of made me wonder if maybe you’re confused about where the WordPress theme files are supposed to go on your server?
I’m honestly not sure what else to tell you from the info I have. I do sort of find it intriguing how much you guys have done with that Child theme. If you’d be willing to give me FTP details and access to your WP admin, I’d be willing to try and update the theme to see what happens and maybe see if anything comes to mind.
If you’d like me to do that, go to My Account here on the forum and you can submit the information to me there.