Gauge condition can be chosen as you like or not? is the Lorenz gauge is the only one correct? If Coulomb gauge can obtained exactly same results as Lorenz gauge for the electromagnetic fields E and B, we can choose what we like, either Coulomb gauge or Lorenz gauge. If use different gauge we get different formula of electromagnetic fields $E$ and $B$, then we have to choose a corrected gauge to get the correct electromagnetic field formula. I am not clear that when we use Lorenz gauge or Coulomb gauge, the result formula for electric $E$ and magnetic field $B$ same or different?
Gauge condition is any human imposed restriction on the functions $\varphi(\mathbf x,t), \mathbf A(\mathbf x,t)$ that does not change electric and magnetic field implied by those potential functions.
For any single physical situation, one can use either potential functions obeying the Coulomb gauge condition or those obeying the Lorenz gauge condition. Both choices give the same electric and magnetic field.