yes, you can do this with routing rules based on the dialed number if you like. You can create as many call handlers in as many levels as you like to accomodate this. Be aware there's no easy way to "segement" the directory such that calls have no access to company A's vs. company B's handlers/subscribers but you can create as many audio text trees as you like and route to them automatically using routing rules.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.