I haven't reviewed the documents so I couldn't really comment on your question except to say that this is really a trusts and estates question. I would post it in that section. This is the family law section.
A trustee owes duties to all of the trust beneficiaries. These duties include the obligation to make the property of the trust productive of income. As long as the trustee's conduct is reasonable in light of the duties owed to all beneficiaries, she should not be second guessed. There should be an accounting of the income and expenses from the operation of the farm. Whether the trustee's conduct in not pursuing an accounting from other partners owning the farm in the past cannot be determined from the facts provided.