Can't Establish Link Between Dreamweaver CS6 and MySQL on Remote Linux Server

unable to establish a connection between my dreamweaver cs6 application and my remote, secured, linode linux server machine. i have followed countless online tutorials to no avail. typically, at the end of these tutorials, they ask you to try to connect to your remote mysql server through your desktop, or another linux machine to ensure everything is set up correctly. the command is:

mysql -u testuser -h -p

and i am able to successfully access the machine through my local linux laptop with this command. but when i try to replicate the process in Dreamweaver's Database MySQL connection, it returns this double error:

HTTP Error Code 404: File Not Found. Here are some possible reasons for the problem:

1) There is no testing server running on the server machine 2) The testing server specified for this site does not map to the http:///_mmServerScripts/MMHTTPDB.php URL. Verify that the URL Prefix maps to the root of this site.

I've tried numerous solutions before reaching out - with hat in hand - hoping for some help. i'm going to give you as much info as i can for what i've tried so far.

first, i rent my machine through linode.com and followed all of their very comprehensive set up guides for installing and securing the machine, as well as their LAMP installation process. i pretty much followed these step by step:

https://www.linode.com/docs/security/securing-your-server/ https://www.linode.com/docs/web-servers/lamp/lamp-on-ubuntu-14-04/

i am running Ubuntu 19.04 btw

what led me to this particular site we're on right now was this similar question:

http://www.webassist.com/forums/posts.php?id=31749

of which i tried the solution and it didnt seem to work.

ive opened up the 3306 port through my firewall "ufw", and i've removed the bind address argument in my my.cfd file.

the fact that i am able to connect successfully through my local linux laptop machine but not through dreamweaver leads me to believe the server is currently configured correctly for incoming connections, but the issue lies itself with dreamweaver's configuration.

also, because my server is currently hardened for security RSA connections only, part of the Site Setup in "Manage Sites" (in dreamweaver) won't work.

i have the site name set as "Registration_Tutorial" and the Local Site Folder is set to : "c:\users\my_name\documents\registration_tutorial\" - when i click "Servers" this is where the issue happens. because of my RSA issue, i am unable to correctly set any of the FTP options. some research shows me there is a bridging solution. the reason i bring this up is because i need to know if this is even relevant to my current issue. is the "servers" part of the site set up strictly for FTPing your changing to your code and uploading it to the site? would this section pertain any relevance to the MySQL issues i am facing? i am leaning towards this being a separate issue. if it's separate, i'm fine with it not working, being that i can upload code changes fine through FileZilla. also, in this "servers" window, I set the "server folder" to : "c:\users\my_name\documents\registration_tutorial", and my web URL is set to: "http://"

i have added some pictures as well.

any help you can provide would be much appreciated. thank you.