Is a living trust the right fit or should we use something else?

None of that goes on a DEED. Where is "here". Who OWNS "here" and has the deed to "here". You say it is Mom's deed. If Mom has the deed to the home, of course she can remain in it for life.
If, say, your Mom is in a second marriage, and lives in the home of a man who wishes to pass the home to his children, but wants Mom to stay in the home throughout her lifetime should he die before her, then this man would go to a Trust and Estate Attorney and create a Trust that give the home to his children, but allows his current wife a "life estate" in the home, meaning she can live there until she dies, and then the children can have to home as dictated by the Trust.
There is no way that a BIL can be forced to pay your Mom 1,000 every December. I have no idea what that is all about. Does BIL owe money to Mom?
In any case, it appears that there is something you are trying to accomplish here, but I don't know what that is. I can only recommend you see an elder law attorney to ask for advice for your Mom and her individual situation. I wish you the very best.

"Added to her deed"?

Has mother been to an attorney and given her home to Brother in law?

Any conditions should have been included at that time.

Consult the lawyer who made the original change.

Consult a trust and estate attorney. That's not trust stuff but rather more like a contract.

Who owns the house? She needs what added to her deed? Those things you listed aren't added to deeds.