Basic Teamviewer connections questions for trial user

Hi,

I am trialling RDM for the company I work for to provide remote support to out customers. They have a wide variety of connection types but the main 2 are teamviewer and RDP. I have created sessions and so forth and they are working but I am struggling to understand what is possible and what is not.

1. Can RDM only connect to a client using teamviewer ID and password and not Windows Login/Windows Password
2. If the above is true, how do you link the domain credential to the teamviewer account?

I setup a new Teamviewer session. ID = 123, Password = Pass
I then setup a Credential for the domain login details and a Typing Macro as $Username${TAB}$PASSWORD${TAB}{ENTER} as per support document.
but it is not working and when I test it to the Notepad as described elsewhere I just get " $PASSWORD$" (ignore quotes)
This is whether I have the Teamviewer session set to Credential repository "My repository" which means Teamviewer fails ( I assume as because I have no password set as its using the credential or with Credentials set to Default allowing me to type in Teamviewer password (which means teamviewer works but then I am stuck.

Maybe there is an alternative to what I am trying. I am just trying to setup this so its
a) Secure. My ideal scenario is passwords are stored and managed by admin so the support staff never actually know the passwords to anything (except senior staff
b) Logged. Full tracking and accountability.

Is there a different Remote Control software that works better with RDM (excluding RDP for now)

Thanks

Brian