Homebrew Cask download failure. SSL certificate problem: certificate has expired
This is documented here, see also https://curl.haxx.se/mail/lib-2020-06/0010.html and https://security.stackexchange.com/questions/232445/https-connection-to-specific-sites-fail-with-curl-on-macos.

The proposed solution is to set HOMEBREW_FORCE_BREWED_CURL

HOMEBREW_FORCE_BREWED_CURL=1 brew cask install netlogo


If you run Catalina you can use

export CURL_SSL_BACKEND=secure-transport


to have curl not use LibreSSL (which seems to have the issue).

You can also remove the entry for AddTrust from /etc/ssl/cert.pem (it's the first entry in the file, just remove all which expired end of May 2020).