We consider the limiting process that arises at the hard edge of Muttalib–Borodin ensembles. This point process depends on θ> 0 and has a kernel built out of Wright’s generalized Bessel functions. In a recent paper, Claeys, Girotti and Stivigny have established first and second order asymptotics for large gap probabilities in these ensembles. These asymptotics take the form P(gapon[0,s])=Cexp(-as2ρ+bsρ+clns)(1+o(1))ass→+∞,where the constants ρ, a, and b have been derived explicitly via a differential identity in s and the analysis of a Riemann–Hilbert problem. Their method can be used to evaluate c (with more efforts), but does not allow for the evaluation of C. In this work, we obtain expressions for the constants c and C by employing a differential identity in θ. When θ is rational, we find that C can be expressed in terms of Barnes’ G-function. We also show that the asymptotic formula can be extended to all orders in s.