  Vortex critical dynamics of the two dimensional XY spin glass is studied by
Monte Carlo methods in the Coulomb-gas representation. A scaling analysis of
the nonlinear response is used to calculate the correlation length exponent
$\nu $ of the zero-temperature glass transition. The estimate, $\nu =1.3(2)$,
is in agreement witth a recent estimate in the phase representation using the
same analysis and indicates that the relevant length scale for vortex motion is
set by the spin-glass correlation length and that spin and chiralities may
order with different correlation length exponents.
