Only the first fet is shorted, the 0.5 ohms didn't save it. Maybe the second fet didn't turn on, but even that shouldn't kill it. M1 is rated 160 amps continuous, should switch in a few microseconds, well before the SOA says there's trouble. Peak possible current was 216 amps with the 108V pack I used. Looking back, I've never hard switched into the inverter without failure, wonder what is happening, could there be a high voltage kickback spike? I rushed the testing, didn't even turn on the scope, traveling soon, wanted to try it first. I'll go much more slowly for round two, maybe put several ohms in series until things look good. Might look at waveforms with a contactor switching the inverter too but with some series R to prevent damage. Still don't see my gate drive as a weakness, but I've been wrong before...