Can you supply a proof of concept?
I understand the what section you are referencing, but code should only be run there if in the admin dashboard.
curl -d "hashtype=1" https://localhost/wordpress/wp-content/plugins/BallastSecurityHasher/BallastSecurityHasher.php
and curl -d "hashtype=1" https://localhost/wordpress/wp-admin/admin.php?page=bssh_config
failed to change the hashtype.