This should make it happen.
(vl-load-com)
(defun c:MleaderBlockify (/ s i e p r n x m)
(if (setq s (ssget "_:L" '((0 . "MULTILEADER"))))
(repeat (setq i (sslength s))
(setq e (ssname s (setq i (1- i)))
p (cdadr (member '(304 . "LEADER_LINE{") (entget e)))
r (getpropertyvalue e "MText/Rotation")
n (getpropertyvalue e "MText/Contents"))
(if (vl-string-position (ascii ";") n nil T)
(setq n (vl-string-right-trim "}" (substr n (+ 2 (vl-string-position (ascii ";") n nil T))))))
(setq x -1)
(if (tblsearch "block" n)
(while (tblsearch "block" (setq m (strcat n "-" (itoa (setq x (1+ x))))))))
(setq n (cond (m) (n)))
(command "_.rotate" e "" "_non" p "_r" (angtos r (getvar 'aunits) 8) 0
"_.block" n "_non" p e ""
"_.insert" n "_s" 1 "_r" 0 "_non" p)))
(princ)
)