Missed Approach Climb gradient and missed approach requirements

[de facto]

I am not familiar with -700 but by memory a 737-900 has a flaps 30 VREF of 151 kts at MLW.(far from the 141 kts in the table you provided).
A -800 at max landing weight may have a flaps 30 Vref of 147-148 kts.
A -800 would have to be around 58-60 T at flaps 30 to have a VREF of about 142, quite below max LDW..

All aircraft in my airline with max ldw of 66360 kgs are cat D as in your table.