Actually you don’t need a singularity to have a black hole. That’s just a mathematical inevitability based on our current knowledge of physics. A black hole is only the result of an object’s escape velocity exceeding the speed of light. And according to general relativity, it should take eternity for a singularity to form anyway, due to gravitational time dilation effects as the black hole collapses. We don’t really know what would happen at the point of singularity.
This may be a stupid question then, but would it not be mathematically possible to measure the mads needed to create a black hole by using escape velocity as the determination, I mean Earth has a mass of 1 let’s say and an escape velocity of x, then just determine how much more mass it would take to make the escape velocity C???