Yep, your DNSSEC is now fixed.
There is another thread
The DNS authenticator only works with Google Cloud DNS. Google Domains doesn’t offer a API that Let’s Encrypt can use.
but if it had worked, that can't be the problem.
Do you have a different error message if you use wrong written credentials?
If not, your credentials may be wrong, perhaps the config file is in the wrong format (utf-16 etc.).
Is your zone name correct?