Yes that's right it's the previous command from history. That way you run ls and see if it's the expected output, then rm to delete.
What you want is "ls /path; rm $_".
Even then, the above is fairly pointless. At the time you look at what you are deleting, it's gone.
1. ls /path
2. rm <esc><.>
(where "escape" "dot" brings up last argument) without the need to fiddle around with dollar signs underscores, exclamation marks, etc. to prevent further mistakes (e.g. "was it $! or !$ ?", shell expansion, etc)