A number of legal theories could be asserted by making motions that will be heard by the court - several are equitable including failure to prosecute, but may be under other terms such as laches, etc.; unknown what the court will do as depoends on all facts and circumstances. Defiance of discovery orders may be another ground to ask for dismissal and preclusion. a local attorney might be able to predict how a specific judge might rule in advance for weighing wheter best to bring motions now or wait longer so the case becomes really old and the eventual request for dismissal more likely to proceed. In Wisconsin, each judge has statistics on the length of probate cases, and there needs to be extensions granted, and that should have a contest process as well. Seek an attorney's advice, whom has knowledge about the local court, to determoine how best to proceed. Maybe not pushing now is better, or maybe the facts including 23 months and defiance of past court orders is enough to push now.
You appear to have a complicated situation and you have not included enough information to give you much guidance. If you do not have an attorney, then you really should have. If you DO have an attorney, then you should rely on the advice of your attorney to determine how best to proceed.
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It sounds like you are already represented by a lawyer. Consult with that lawyer first. It sounds like your lawyer may want to move the court to dismiss the complainant's claim for failure to prosecute and/or as a sanction for failing to follow the court's orders. Consult with your lawyer. Good luck.