Probably. If you are years into this with no progress, no discovery and no petition for removal, you might need an attorney with more litigation experience.
As far as challenging the trust, there is a good chance the statute of limitation has run on that. That said, financial elder abuse statute is four years. That might be explored. While I really dont like to advocate malpractice actions, you may also have to consider that option if the facts are as good as you say in your favor.
Regardless, you need to act to protect your rights no matter what that means you need to do. Dont sit back and wait for time to run.
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Find an attorney experienced in these matters and request a consultation. Second opinions can be valuable.
As an aside I have never seen an undue influence case litigated successfully without engaging experts like a forensic psychiatrist.