I went through the same trials that the OP went through, and was also given the "Your case is being closed", and was told they would not pursue any further action on my account.
The biggest problem is their inconsistent lapsed Plus policies. If you have a save in the cloud, your Plus expires, and then you resubscribe, they explicitly say that the saves will be there. This creates the expectation that free content will be again free when Plus is reactivated, which is also confused by their FAQ examples that explain that "if the content is still free" you can re-download it".
Best of luck man, but after what I went through, I'm not very hopeful.
EDIT - Resolution steps attempted:
Reactivation of console, Download on another console. Factory reset of console. Download through system download history, download through SEN history.