Any party to the proceeding, before or after filing objections to the probate of the will, may examine any or all of the attesting witnesses, the person who prepared the will, and if the will contains a provision designed to prevent a disposition or distribution from taking effect in case the will, or any part thereof, is contested, the nominated executors in the will and the proponents and, upon application to the court based upon special circumstances, any person whose examination the court determines may provide information with respect to the validity of the will that is of substantial importance or relevance to a decision to file objections to the will.
