You want to use a dedicated sql server, however, you are unable to establish a connection to the SQL server.
You get "Error 80020009" when testing the connection.
TDAD (Symantec Endpoint Threat Defense for Active Directory) version 3.6 and below do not support connection to SQL using TLS 1.2
TLS 1.2 enabled on SQL server
To have TLS 1.2 compatibility, please upgrade TDAD to version 18.104.22.168