for the 2.1 radius of the gravitational simulation is this correct: Here is my data- Impulse 4385, Max 9194, min 4385. Min KE=1/2 mv^2=1\2(1kg)(4385)^2, Max KE=1\2(1kg)(9194)^2, dPE=mg dy= 1kg(9.8m/s^2)(9194-4385)
Your velocities are in m/s and you should include those units in your calculations. Otherwise you have the right expressions for KE. When you complete the calculations you will get units of kg m^2 / s^2, or Joules.
9.8 m/s^2 is the acceleration of gravity at the surface of the Earth. The acceleration of gravity drops off as you get further from the Earth so you can't use 9.8 m/s^2 in this calculation. m g `dy works only close to the surface of the Earth, where g doesn't change by much.
There are no nonconservative forces acting on the satellite, so the change in PE will be equal and opposite the change in KE. Find the change in KE from your figures above.