That is not a problem . You can go ahead and add node-2 in cluster . there are many files in UCCX which have IP address of node-2. If you will add new node-2 in cluster it will update those files with New IP address . After installing new node-2 if you see DB replication issue then contact TAC.
If you have already open TAC case then you can ask for "removenode2.sh" script it will completely remove node-2 entry from node-1.
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.