Ex-wife In Hospice And About To Die, Leaving Estate To Her Boyfriend. Divorce Decree [possibly] Imposes "constructive Trust" On The Estate.

Location: Oregon, USA

Briefly...

• My ex is in the hospital, in the last stages of dying. (Heavily medicated and non-responsive.) Her prognosis is terminal and she is expected to pass in the next 24-48 hours.
• Everyone involved in this situation has, for now, agreed to not discuss estate matters until after she passes.
• Despite this, her boyfriend of 5 years has made it known that she set up a trust sometime in the last year or so leaving everything to him. (They've lived together for 3-4 years but are not married.)
• Estimated estate value is ~$0.5-$2M
• My ex and I divorced in 2014. We have one child together, who is currently 16 years old.
• Our divorce decree orders each of us to maintain a $500K life insurance policy "naming the other party as trustee on behalf of the minor child until the child attains the age of 18"
  • I have complied with this provision
  • I suspect my ex has not, but do not [yet] know that for a fact
• The decree also stipulates the following:

In the event either party violates these insurance provisions, a constructive trust shall be imposed over the estate as well as the proceeds of all insurance owned by the party at the time of their death to secure payment of this insurance obligation.

• The boyfriend doesn't know about the terms of the divorce decree
• I haven't yet reached out to my divorce attorney about this, but will be doing so ASAP.

My questions are as follows:

1. Assuming I'm right about my ex not having a life insurance policy, am I correct in thinking I (on behalf of my child) have a claim to a portion of the estate sufficient to cover the $500K insurance benefit?
2. What does "constructive trust" mean in this context?
3. What do I need to be doing now (over the next 1-3 days) to best protect my child's interests?
4. How does the estate settlement process work? At what point should I disclose the terms of the divorce decree?
5. What am I missing? What don't I know?