MATLAB: Pole at 0.1 rad/s contributing to nothing on the Bode Plot - Why?
In the first calculation you correctly calculated the gain before the second pole to be 48000/100

On the second example the gain before the second pole is 48000/(100*0.1). So it is 20dB higher. This compensates with the higher attenuation of 20dB for the additional pole, so at w=1 the gain is unchanged.

To avoid these issues it is better to use a normalized notation where each pole is in the form (s/n + 1).