Are the timeshares deeded properties or points? Deeded properties can be transferred into your trust via a new deed. Other types of timeshares will be governed by the timeshare agreement/contract so contacting the timeshare company would be the best place to start.
Generally an individual has a right to name any person or organization as a beneficiary and exclude anyone if they choose. However, because Washington is a community property state, you may be able to make a claim for your mother's community property interest. You should consult with a Washington estate/probate attorney to see if Washington law provides for such a claim and if there is an applicable time frame for this.
I agree with the answers provided above. Also look for language in the trust which may allow for either one of the settlors/trustees to act independently on behalf of the trust. However, even if the trust does allow for this, the escrow company may still require your mother to be formally removed as trustee per the procedure stated in the trust instrument. It is likely that you will need an attorney to review the trust as well as prepare any required documentation.
As a beneficiary of the trust you are entitled to certain information, including a yearly accounting. I recommend that you ask for an accounting in writing if you haven't already been provided with one.
Naming a guardian is crucial but so is deciding who and how someone will be in charge of the assets on her behalf as well. It is important to consider how beneficiary designations on bank accounts, life insurance policies, and retirement plans should be done to coordinate with the guardianship nomination. I advise that you consult with an attorney regarding these issues.
You are entitled to an accounting and can request one in writing. I would recommend that you deal directly with the attorney who represents him in the administration of the estate. If you do not receive the information you are entitled to, I would advise you to hire an attorney to represent you as a beneficiary. Please contact my office directly if you would like to discuss in detail.
At the County Recorder's Office where the property is located it is possible to obtain copies of all of the grant deeds to see how they are titled.
As far as proving your claims of duress and undue influence, those are generally very difficult to prove. Also the trust may contain a No Contest Clause which if enforced would disinherit anyone who contests the trust.
Generally copies of Powers of Attorney are able to be used unless a financial institution or other entity specifically requires an original. If you are unable to get a copy, then you should have your husband execute new ones. However, he can only do so if he still has the necessary mental capacity to execute the documents. Otherwise, a conservatorship is necessary.