Hi, Something for you.
Working Sample

Code Here..
Try with 'MTB'
(vl-load-com)
(defun c:mtb (/ hnd urpt str msp msp)
(defun rh:d2r (d) (* pi (/ d 180.0)))
(if (setq ss (ssget ":L" '((0 . "MULTILEADER"))))
(progn
(repeat (setq i (sslength ss))
(setq hnd (ssname ss (setq i (1- i)))
str (vlax-get-property (vlax-ename->vla-object hnd) 'TextString)
msp (cdr (assoc 110 (entget hnd)))
mep (cdr (assoc 10 (entget hnd)))
)
(vla-getboundingbox (vlax-ename->vla-object hnd) 'mn 'mx)
(setq urpt (vlax-safearray->list mx))
(command "_.rotate" ss "" msp "_reference" mep msp (polar msp (rh:d2r 180) 1000))
(if (not (tblsearch "BLOCK" (substr str 29 6)))
(progn
(command "_.-block" (substr str 29 6) urpt ss "" )
(command "_.-insert" (substr str 29 6) urpt "" "" ""))
(prompt "This Nme of Multileader already done")
)
)
)
)
(princ)
)
I tired with finding Multileader Base point..
I hope, It is Help to you.
Lips file here