While the trees were declining, I looked very carefully and did not see any holes, borers, or powder.
When I cut one of the two down to a stump, I did not see any unusual discoloration, other than what I expected to see with a tree drying out.
A couple of months after the tree was dead and cut back to a stump (a little over a meter high), I saw some very fine white dust no the stem close to the base. I still did not see any borers of holes (I didn't take a magnifying glass to it)
This past week, I cut the stump as low as I could and burnt the rest in preparation to reuse the spot.
I really don't think it is Laurel Wilt but in the event it was I want to take the best course of action to minimize risk to whatever I plant on the spot.
I hope Carlos sees this post and responds. Interestingly, the tree in question was a Lula that I cut back and topworked to Oro Negro on Carlos's recommendation and with budwood I got from him. It was loaded with fruits for the first time when it started to die back. I was looking forward to getting and trying the fruit last year.