No, that's not right. Because of the spring connnection between tandem
axles, a flat tire will move the force to the other axle, not the jack. That puts unequal weight distribution at the axle point...right where the slide is. Poor decision to use slide supports.
I don't know how your trailer axles are but mine are connected to the frame and if the frame is supported 1-2-3 or 4 flats are "not" going to move the frame or slide.
Ever set up a mobile home then take the axles and tires off, I have and it's the same concept... That's extreme but 4 screw jacks rated at 6500 lbs each are more than capable of holding the trailer in place on solid ground without worry of a flat tire.
By the way, I've had it happen without any movement at all with corner jacks..... What is your actual experience with a flat tire with 4 corner jacks down?????
Your guessing I'm not!