Unfortunately, expect (from any language) is not really suited to something that isn't a standard screen buffer response. I've seen some implementations that attempt to deal with cursor position updates such as curses but the results are not always effective.
I feel that your time would be better spent researching what operations the curses app is giving you a menu for configure your application do do those items yourself. I've found that nearly every curses menu has a companion cli cmd, or is a front end for one.
If you can share what the curses menu is for the community might be able to assist you with whats going on in the background. If you cant because it's something home grown, you should be able to trap whats going on in the background with something like
Hope this helps.