Okay... I have kludged way of checking if a Schedule Style is in the drawing...
I snag the list of schedule styles from the text screen and check the list.
The following is the lisp code to do this.
Surely their is a better way...
(setq logfilemode (getvar "logfilemode"))
(setq filename (getvar "logfilename"))
(setvar "logfilemode" 0)
(vl-file-delete (getvar "logfilename"))
(setvar "logfilemode" 1)
(command "-scheduleadd" "?" (command))
(setvar "logfilemode" 0)
(setq textscreen (readfile filename))
(setvar "logfilemode" logfilemode)
(setq exists (not (null (member ScheduleName textscreen))))