Trying to replace Kerridge Windows DW terminal emulator w/ something else

This one is a bit hairy. I am trying to connect to an old Unix SCO server and the terminal software that was used is supported only up to Windows XP.

The software is Kerridge Windows DW (DW Terminal Emulator for Windows).
That software is edn of the line and no longer supported, so upward compatibility for this server is nil.

So far I tried telnet to the server in Windows and it works but it won’t take the commands.

Tried PuTTy and that gets up to login screen, logs in and hangs.

Any ideas on software that’ll run on Windows 7?

Thanks in advance!