I know for a fact that my mother’s (94) trustee is not acting in her best interest legally and morally, and this trustee is paid. Thoughts?

People, your BS meters should be going off. I'm with ZippyZee!

Here is the problem with making someone Trustee of your Trust. A Trust is made by YOU for yourself. You are the TrustOR, the TrustEE, and the GranTOR. When, for reasons of your own you appoint another to be the Trustee it better be for good reason, because you cannot withdraw or change this. It is done, and only that Trustee can now act for the Trust. This was explained to us when my brother was diagnosed with probable early Lewy's Dementia and asked me to become his POA and the Trustee of his Trust. He wanted me to take over ALL financial matters, bills, sales, protection of his assets, investment of his assets because it was almost certain he would descend slowly into incompetency. When he did this the Lawyer said "Are you CERTAIN you want your sister to be the Trustee of this Trust, because once you do this she can sell the GOLD out of your TEETH, and there is nothing you can do about it."
POA is a Fiduciary Responsibility, but a Trustee is just that, appointed to manage a trust and he can manage that trust however he decides to. The Trust is not for the benefit of the original grantor. It is simply a Trust.
You really need to advice of an elder law attorney or a trust and estate lawyer so that you can understand what has happened here, and what can be done about it. Almost certainly, with assets held in a trust, the answer is VERY LITTLE. As to other assets not in the Trust, and there may be some, they would be managed with POA, and POA DOES HAVE a fiduciary responsiblity. So if fraud is suspected with assets outside of a trust, something CAN be done. Take evidence of fraud to elder law attorney to find out how to proceed.
This is all assuming that your grandmother actually made your adopted sibling the Trustee of her Trust, removing herself as Trustee of her own Trust.
You are a bit confused by Trusts overall I do believe because you mention your "own" Trustee. If you have created a Trust and are the Trustee and the Grantor then YOU alone have power over that trust. If someone ELSE created a Trust FOR YOU and appointed a Trustee to manage that, then you do not have the power to manage the trust being managed for your benefit. That most often happens in the case of a mentally disabled person incapable of managing his or her own trust. I doubt that is the case for you.

I'm getting Déjà Vu here.