But I still don't see how you define an estate. Are you defining it for CA family law purpose or for estate tax purpose? Either way, I don't see how you can include any property in a simple none-grantor irrevocable trust in the grantor's estate, unless it was established while the divorce action was looming or undergoing, or when the grantor was preparing for his death. Of course, it is also possible that there is a statutory period defined by CA law to pull the assets back from the trust, just like IRS could pull back the life insurance proceeds from a special irrvocable trust (ILIT) if the life insurance becomes trusts assets within 3 years of the grantor's death. However, I don't see any from your post.
We all know case laws are very specific. It may apply to one particular of trust with soe specific language, but it does not mean it would apply to all the trusts. I've seen IRS ruling that subjected a trust for millions of dollars simply because the trustee's dicretion is too aboard. A almost identical trust with additional limitation on the trustee's discretion as "...for support and maintenance" was okay, however.
That's why I insist that trust document and background are very important in this case. I am also very puzzled by your claim that there is no trust document yet it was settled before the deceased's death. Who drafted the trust document or is it a constructive trust?