This looks like it could be a url rewriting issue. Could you send a screenshot of what happens when you manually try to access http://10.80.3.35/healthcheck/status ?
Did you configure nginx as mentioned in the article? Did you restart it / or reload it after ?
[PASS] PHP version 7.0.25
[PASS] PCRE compiled with unicode support
[PASS] The temporary directory and its content are writable
[PASS] The public image directory and its content are writable
Config files
[PASS] The core config file is present
[PASS] The database config file is present
[PASS] The email config file is present
[PASS] The application config file is present
Core config
[PASS] Debug mode is off.
[PASS] Cache is working.
[PASS] Unique value set for security.salt
[PASS] Unique value set for security.cipherSeed
[PASS] Full base url is set to http://10.80.3.35
[PASS] App.fullBaseUrl validation OK.
[FAIL] Could not reach the /healthcheck/status with the url specified in App.fullBaseUrl
[HELP] Check that the domain name is correct in app/Config/core.php
[HELP] Check the network settings
SSL Certificate
[FAIL] SSL peer certificate does not validate
[FAIL] Hostname does not match when validating certificates.
[WARN] Using a self-signed certificate
Database
[PASS] Configured to use a supported database backend
[PASS] The application is able to connect to the database
[PASS] Not using a prefix for database tables
[PASS] 20 tables found
[PASS] Some default content is present
[PASS] The database schema up to date.
GPG Configuration
[PASS] PHP GPG Module is installed and loaded
[PASS] The server gpg key is not the default one
[PASS] The environment variable GNUPGHOME is set to /var/cache/nginx/.gnupg
[PASS] The directory /var/cache/nginx/.gnupg containing the keyring is writable by the user the webserver is running as.
[PASS] The public key file is defined in app/config.php and readable.
[PASS] The private key file is defined in app/config.php and readable.
[PASS] The server key fingerprint matches the one defined in app/config.php.
[PASS] The server key defined in the app/Config.php is in the keyring.
[PASS] There is a valid email id defined for the server key.
[PASS] The public key can be used to encrypt and sign a message.
[PASS] The private key can be used to decrypt a message.
Application configuration
[PASS] Using latest passbolt version (1.6.5)
[FAIL] Passbot is not configured to force SSL use
[HELP] Set App.ssl.force to true in app/Config/app.php
[FAIL] App.fullBaseUrl is not set to HTTPS
[HELP] Check App.fullBaseUrl url scheme in app/Config/core.php
[PASS] Selenium API endpoints are disabled.
[PASS] Search engine robots are told not to index content.
[PASS] Registration is closed, only administrators can add users.
[PASS] Serving the compiled version of the javascript app
[PASS] All email notifications will be sent.
Development Tools (optional)
[PASS] Phpunit is installed
[PASS] Phpunit version is 3.7.38