I changed the user name to "admin" in the MySQL controls on the control panel for my site and in the wp-config.php file of the blog database. I then uploaded this revised file to the subdirectory
Nowhere, in any of the documentation I provided links to, my suggestions, or the instructions, does it tell you to do that for installation. I believe you are still trying to go your own way rather than follow the installation instructions, or any guidance.
Please carefully re-read what I have said, then re-read the installation instructions, and take it one step at a time.
The only name and password that goes in the wp-config file is the database user name and the database users password provided to you by your hosting service, that allows you to access your database. I can assure you, it most probably should not be "admin". It has no relevance to your wordpress user name or login.
Follow the directions listed here exactly. Use the page as a reference. Do what it suggests, one step at a time. This really is a five minute process.
Start with a fresh database. Empty the existing tables in your database. Start with a fresh wp-config.php. Fill in the information based on the instructions. The user name and password is not what you want it to be, but what your host has told you it is. This is for access to your database. Not the user name and password you want to use for wordpress. THEY ARE NOT THE SAME.
Delete the files you uploaded to your blog. Upload a fresh wordpress package to your web space. open your browser, go to your site.
If the data you provided in wp-config is correct (based on the information assigned to you by your hosting service) and your server meets the minimum requirements, wordpress will now install.
It's like putting together a model airplane. Follow the directions, one step at a time and it looks good. Throw them away and do it yourself, and you probably wind up with something less than the picture on the box. Short of that, perhaps your hosting service has a method by which they can do the installation for you. Many do.