Lets look at your model..All HB's computations of the farcical miasma lead to a singularity of theoretical absolute density.
F=ma clearly shows that if you double the force affecting a mass you DOUBLE the acceleration.
F=GMm/r² does NOT even begin to satisfy that.
Above we see that you can double the force by doubling M or m.
You could double the gravitational acceleration on Earth by doubling the mass of Earth.
Apparently gravitational force for a 2 kg lump is twice that of a 1 kg lump.
The gravitational force is doubled, why is not the acceleration doubled?
In reality your model is a miserable failure of gibberish in the language of mathematics.