Tried this on NetBSD-1.3. (1.3A from about 3 weeks back to be
accurate) on an alpha.

0. run screen.

1. create a second window (so the kill doesn't delete the last window)

2. tty (ttyp3 for me)

3. emacs

4. ^xk (kills window 1).

5. ^xc (create a new window). No ghost image.

6.  tty tells me this is ttyp3 again.

Sorry- I can't reproduce you're thingie.