Idk what you're trying to say, so I'll try to interpret it in 3 ways.
1. The attack can kill everyone within a 10km radius
2. The attack does a hole with a radius of 10km
3. The attack destroys everything within 10km
1. I'm not sure how to do this one so I'll use inverse square law, which makes the result 1.47 kilotons of tnt (Low 7-C) though this one might be wrong
2. I'll make 4 ends here, 1 for stone fragmentation, 2 for violent fragmentation, 3 for pulverization and 4 for vaporization (IIRC hole depth is assumed to be diameter * 0.18)
2 (1): 685 megatons of tnt (7-A+)
2 (2): 5.9 gigatons of tnt (6-C)
2 (3): 18.3 gigatons of tnt (6-C)
2 (4): 2.2 teratons of tnt (Low 6-B)
3. I'll do the same as 2
3 (1): 4 gigatons of tnt (High 7-A+)
3 (2): 34.5 gigatons of tnt (6-C)
3 (3): 107 gigatons of tnt (High 6-C)
3 (4): 12.86 teratons of tnt (6-B)
Those results will have to be divided by 2.
Option 1: each character scales to 735 tons of tnt (8-A)
Option 2: They scale to 342.5 megatons of tnt (7-A), 2.95 gigatons of tnt (High 7-A+), 9.15 gigatons of tnt (6-C) or 1.1 teraton of tnt (Low 6-B)
Option 3: They scale to 2 gigatons of tnt (High 7-A), 17.25 gigatons of tnt (6-C), 50.35 gigatons of tnt (6-C), or 6.43 teratons of tnt (Low 6-B+)