I think it's time to ditch all this electronic crap and go back to relying on mechanical hardware and experience. No more computers. Computers take the skill out of everything and add too many potential problems. Have backups and ensure they are independent of the mains. From engine problems to computer problems, something that takes out a main system should not be capable of taking out the backup. And accident or not, the timing of the failure is mighty suspicious.
It looks like after they lost power and it came back on that they may have dropped it into reverse and gave her the onions with all the black smoke coming out. Maybe that is what caused the change in direction, reversing so hard. I don't know the currents in that area, but going full reverse will make a boat turn. But why did it lose power again? And isn't the tiller hydraulics on a separate generator? I think someone needs to have a "sit down" with the electrician. If something kills the power, it should blow a fuse, and when the backup comes on, the failed circuit should be left off until diagnosed. Losing power twice means they tried giving power to a bad system twice. Why? What was that system? It will be interesting to see what the report says.
Here's a simple plan... Every ship over a certain mass has a 3-tug escort through the channel just in case someone needs a little push.
Another question I have is do these anchors have brakes or does the entire chain need to be released? I have heard that it is the weight of the chain on the sea floor that does most of the braking, so maybe they didn't have enough room for the anchor chain to get a firm grip on the bottom.