CAD-based monitoring and recording are based on the phone mirroring the packets to the PC port. You need 2 things for it to work: the phone spanning the traffic to the PC, and the PC able to put its network card into promiscuous mode to receive the traffic.
Make sure that the phones are configured with the option "Span to PC Port" enabled. Since it sounds like this was working previously, that is probably not the issue, but it is the first thing to check.
If the phones are properly configured, try running Wireshark on the workstation and make sure the phone is actually sending the spanned packets, and that the PC is able to receive them. If you are not receiving the packets, maybe try substituting one of the old PCs, and see if that is able to receive the packets.
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.