In a proper H bridge, two FETs are always on. That "shorts" out the motor, Hence a diode. For the very short transition period, the internal diode of the FET can be used in some cases. That 140A has a one in a circle after it. The secrets of the ages is found in that ONE.
In your circuit the turn off pulse of likely 300V will travel through the FET diode and through the gate resistor. Once that voltage goes much above 20V the gate will be blown out. In the best result the transistor avalanches C-E and recovers, maybe it shorts out. Worst case it shorts C-B and blows out your micro. What I like about electronics is that it always knows what to do. We have to wonder.
So you are the antenna guy. Hope you haven't decided to use that resettable breaker. Those are just good to prevent fires. So how did this turn to a single FET? Maybe you told us. Frankly my eyes glaze over after a couple sentences. It is just blah, blah, blah, blah, blah after that. Had you taken my advice on that thread, it would have been done by now.
So get yourself a $8 UNO, there is nothing simpler to use and write 20 lines of code. Use a N FET with an opto isolator with the diode across the FET. Sample the current with a less than .1 ohm resistor in the source. Filter that with a resistor and a cap and read the A/D value. With a potential thousand counts, 50-100 will be enough to decide a current limit. A DPDT relay to set direction and a couple time delays to prevent nasty arcing. Use the UNO 490hz PWM to ramp up and down the motor. No need to tear up the gearbox or antenna with rapid movements. Four days at most for an extreme neophyte to do this.