@David_Lynn I am super glad that you figured it out. Now you can mark yourself as the Solution! 
Sweet!
I think the reason it wasn’t writable was because it was tying to upload above the Root of your WP site which is off limits to anything within the public_html folder. That URL string looks like your cPanel Root directory & “bosnaweb08a” is the account name.
Really glad you figured that out.
Yeah the default File / Folder permissions for WP are 755 Folder & 644 Files.
here is a bit more information on that Changing File Permissions – WordPress.org Documentation