"SQLSTATE[HY000]  Access denied for user" - caused by characters in the password2 users found helpful
SQLSTATE[HY000]  Access denied for user 'superfunbox_admin'@'localhost' (using password: YES)
To see if it was a configuration issue, I installed 220.127.116.11 with Softaculous to get a working database.php file. Nothing about the settings were special, except for the Softaculous generated MySQL password. The password was not very complex and had no special characters.
I decided to change the MySQL password to something less complex. The less complex password allowed me to install 18.104.22.168 properly.
The password I was using for MySQL was:
The password I changed it to that worked: