I ended up fixing this in a completely different way. I overrode dired-find-file and dired-mouse-find-file, as follows ...
(defun my-special-function ()
(message "my special function")
(defvar my-dired-advised nil
"*my dired stuff is already advised")
(defun my-dired-mode-hook ()
You replaced the binding for <mouse-1> with a binding to your command. That should be fine, but it's not a "remapping" (which is about commands or faces, not keys).
Remapping a command is about doing something like this:
(define-key dired-mode-map [remap dired-mouse-find-file-other-window] 'my-special-function)
That remaps the keys bound to ...