I know of a local racer who once busted a sensor board on a brand new motor, very first pack on the track... sometimes it's like winning the lottery (or antonym in this case, ha!) and he was running a different brand other than Trinity... fact is I've seen pretty much every brand of motor at the tracks in my area have a sensor board go out on them.
To be honest, I may have had a few bad boards go out on me as well when I first got into racing... I was too intimidated at the time to do any testing on the motors, I simply threw them away and bought a new one... I've probably ran 4-5 different brands of motors over the years.
Am I currently a Trinity Fanboi? Sure, but honestly there are probably 2-3 other brands that I wouldn't hesitate buying today if Trinity was out of stock for the parts I need for stock racing. Fortunately I'm not sponsored by Trinity so I can buy whoever has the next fastest motor at the time.
If it were me, I'd replace the sensor board, re-shim it and give the motor 1 more chance... if the sensor board breaks a second time, then you know the brand is unlucky for you.
I also checked and they do show some sensor boards in stock here:
https://www.teamtrinity.com/Monster-...ring_p_56.html
I do agree that it's questionable if Trinity might have had a bad batch of improperly shimmed rotors because both of mine needed 0.2mm of spacers added, but I am not an expert, I'm sure some Trinity rep will come on here and have some sort of justification on tolerance for how much contact is allowed with the magnet on the rotor.
My lesson learned from this experience is that I will never install a brand new motor ever again without first checking the shim on each motor, regardless of the brand of motor.