We prove an equivalence between the Bryan-Steinberg theory of
$\pi $
-stable pairs on
$Y = \mathcal {A}_{m-1} \times \mathbb {C}$
and the theory of quasimaps to
$X = \text{Hilb}(\mathcal {A}_{m-1})$
, in the form of an equality of K-theoretic equivariant vertices. In particular, the combinatorics of both vertices are described explicitly via box counting. Then we apply the equivalence to study the implications for sheaf-counting theories on Y arising from 3D mirror symmetry for quasimaps to X, including the Donaldson-Thomas crepant resolution conjecture.