I depend on the logic of the situation - what a coldly rational evaluation of the situation was. Ethiopia made a business calculation. Just like they did to invade the Tigray region. Boeing, et al, did not foresee that a mass casualty event would be acceptable to a typical airline, but underestimated what invulnerability allows an actor to consider.
If Ethiopia had halted all MAX flights to retrain all their pilots for that brand new centerpiece acquisition, that would make their political position weaker and cost them for the retraining and loss of ticket sales. Skipping training was a positive. They knew that if the plane crashed from mishandling due to MCAS inputs that would be a bargaining position. Those considering a war against civilians certainly aren't concerned with a handful of passengers.
Why not proceed -- you claim "roulette," but there was no gambling at all as they controlled the house or, in this case, the narrative.
That pilot who did quit Ethiopian related a case where an engine was thought to be leaking fuel - a ramp worker reported a far larger than normal amount of fuel pooled under an engine. The pilot called for someone to check the engine, which would delay the flight. He reported he was told that a leak was not his concern - if the engine caught fire the airline would seek compensation from the engine maker.
That's the sort of calculation they would have made about MCAS. I don't currently believe they looked forward to a crash, I would say they did not care if it happened because the outcome was a benefit. For certain the Chief Pilot wasn't on that plane.
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Perhaps I misread this section then (my bolding):
Senator Ted Cruz has taken a leading role in exposing Boeing’s criminal behavior. During
investigative hearing on the two crashes, Senator Cruz exposed what Boeing had done through
pointed questions to CEO Muilenburg:
The testimony here today has been quite dismaying. I want to focus on the
text exchange that has been referred to and has been publicly reported on. There
was a text exchange between Mark Forkner, who was then Boeing’s technical
pilot for the MAX—chief technical pilot for the MAX—and Mr. Gustavsson, who
in 2018 was promoted to be Boeing's 737 chief technical pilot."
Mr. Forkner: [...] MCAS is now active down to M .2. It's running rampant in the sim on me
I posted what Ted Cruz went on to say in the earlier post.
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"not for training purposes"
is basic cover to prevent anyone half-remembering what was shown coming to sue them over some mishap. Very much like the YouTube lawyers who emphasize they are not to be taken as legal advice while they are pointing out laws and precedents that might apply to a case they are exploring. Even in engineering, particularly civil and structural (buildings and bridges,) engineers will emphasize that advice is as-is and must be compared to applicable regulations which can vary with locale.
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I think this action is against the wrong party, but the correct party is invulnerable. Being "false and misleading" did not cause ET-302 to crash. Putting improperly trained people in control of an aircraft with a known, sometimes fatal but easily controllable, defect caused ET-302 to crash. Part of that improper training has been complacency over trim runaway containment training, but that was exactly what the communications from Boeing and the FAA stated was the problem.