No offense, but leaving a 100 lb motor hanging on a bracket with no
support for a trip of that distance is - well, stupid. No other word
for it.
Another word for it might be.....unfortunate.......
Being a sailor, this guy might not be familiar with all the cracked outboard
brackets that happen when powerboats come back in from offshore and take a
pounding, so he didn't prep for that.
As often as not, I suspect that the bracket cracks are the cumulative result
of metal fatigue, rather than a one-time stress, and an outboard bouncing
along for over a thousand miles might be what pushed the bracket to the
limit. Who knows, it might have been on the verge of cracking when the trip
started.
Unless there is some evidence of the motor being backed into something,
methinks you protest too much.