No monitor state information for slave server using Stunnel

Hello

Debian 9 Stretch
ISPConfig version 3.1.14p2
Multi-server setup

On the Monitor page all servers show OS and ISPConfig version along with all state and log files except for mail server.
Mail server is shown in green on the overview page but no information is available for any state or log files.
Mail server is a remote server connecting over WAN using Stunnel.

Initially after installing the job queue does not update unless I create a new MySQL user on the Master server for the slave mail server.

On the slave I ran:
/usr/local/ispconfig/server/server.sh
and I got many errors like this:
WARNING - There is already a lockfile set, but no process running with this pid (2542). Continuing.
PHP Warning: mysqli_real_connect(): (HY000/1045): Access denied for user 'ispcsrv6'@'localhost' (using password: YES) in /usr/local/ispconfig/server/lib/classes/db_mysql.inc.php on line 85

Therefore I created an additional user on the master server:
CREATE USER 'ispcsrv6'@'localhost' IDENTIFIED BY 'password';
and GRANTED All privileges to above user

I found the user 'ispcsrv6' in file '/usr/local/ispconfig/server/lib/config.inc.php' on the slave.

After creating this user on the master server the job queue syncs and everything works except the status monitor

When I installed ISPConfig on the Slave and it asked for the Master server details I used the following:
MySQL master server hostname []: 127.0.0.1
MySQL master server port []: 24
MySQL master server root username [root]:
MySQL master server root password []: ****
MySQL master server database name [dbispconfig]:

This worked and installation completed.

My Stunnel conf files are below:
Master Server Stunnel .conf:
key = /etc/stunnel/privatekey.pem
cert = /etc/stunnel/certificate.pem
[mysql]
accept = 0.0.0.0:44323
connect = 127.0.0.1:3306

Slave Server Stunnel .conf:
client = yes
verify = 4
pid = /stunnel.pid
CAfile = /etc/stunnel/certificate.pem
[mysql]
accept = 127.0.0.1:24
connect = xxx.xxx.xxx.xxx:44323

Where xxx.xxx.xxx.xxx is the Public IPv4 address of the Master server.

Is it possible for the status monitor to work over Stunnel?
Should creating a new user (ispcsrv6) for the Slave on the Master be necessary?
How do I correctly configure a remote server to use Stunnel?

Thank you