Is the CG really too high. That's basically 2 big guys, or 3 medium guys standing up behind the driver. For a boat like that, it is unlikely that doing that (all standing up at once) would cause a significant problem. And with a tractor that's secured over the center of the boat, it's less of a problem as it's not moving, and if it becomes unsecured and goes to one side, it's likely going off the boat before the boat capsizes.
Unfortunately, it doesn't work like that.
It's too involved to go into here, but in brief carrying a significant load at the height raised above deck alters the CG of the boat significantly. Because boats move through a dynamic medium (water), they experience multiple degrees of freedom of movement (roll, pitch, yaw, and heave) sometimes simultaneously. The higher CG will more readily and dramatically shift outward under certain circumstances, and if it moves past the hull's center of buoyancy the vessel will become highly unstable and possibly capsize. This would happen in a blink.
He didn't give boat details, but it looks like an ETEC 90 HP engine (maybe?) which suggests to me it's a fairly light 16-18' hull with about a 7.5-8' beam. That size boat doesn't have a lot of room for error when raising the CG up like that.
Again, I'm glad the OP made it safely. But I don't recommend attempting that, certainly not in anything but the calmest conditions, and not with any passengers who could move about and trigger dynamic instability.
SOLD: 1966 JD 110 Round Fender
Integral Sleeve Hitch, Model 42 Blade,
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