Technically, because of the KJ's structure, you cannot exceed the maximum GVWR anyway (not legally, at least...but not being a DOT-inspected vehicle...nobody will know)

My point is

2300lb/tire=4600/axle, or 9600 total.

So basically

with the P-metric Toyos
you can have a GVW of almost 5 tons, so I do not see a problem running them at max pressure at that weight.

The broad at Toyo obviously doesn't know a tire from a torque wrench...