Unable to send CTRL-R keystroke in Console because it's intercepted and used by the application. This appears to be a keyboard shortcut for renaming the tab. (The Rename Tab menu item doesn't indicate this shortcut exists.) This simple keystroke is sometimes necessary when connecting to *nix machines when using Lynx and various editors.
Since CTRL is often used by terminal-mode applications, perhaps instead using something with ALT in it would be more prudent in a terminal application?