Roger is correct - no Telnet in current products. SSH is your only command line over the network option. Here is the API guide for reference. https://www.cisco.com/c/dam/en/us/td/docs/telepresence/endpoint/roomos-1117/api-descriptions-roomos-1117.pdf...

It should use standard windows drivers. We have hundreds of users using the desk series with USB passthrough and drivers have never been an issue, this should behave the same.  

IX's are not supported in CH at all (they never were), and the other devices are all end of support. You can still register them, but you'll get messages saying they are not supported. 

If both systems are doing the same thing, I'd guess you've found a bug. What SW version are you running on these? You probably should open a ticket with TAC if you haven't already, this is unlikely to be a configuration issue.