If the Bristell is anything like the Evector Sportstar I have flown then the stall would most probably appear to be relatively benign. The Sportstar looks roughly similar to a Bristell.
When I was endorsed on the Sportstar my (grade 3) young instructor said "watch this" and proceeded to a power off stall. The aircraft stalled with no warning and then just mushed straight and level with aileron authority and set up a very high rate of descent indeed. We recovered by adding power. We dropped about 500 feet mushing before power was added.
I never tried a power off stall and a power off stall recovery from a mushing descent.
I have never flown the Bristell and I don't know what happened, but I am innately suspicious of claims that certain aircraft have no vices or benign handling characteristics. The accident aircraft looks to have contacted the ground flat, at a high rate of descent and with very little forward speed. This made me think of my experience stalling a Sportstar.