Determine whether the torus bundle example admits stably exotic fillings

Determine whether the nonorientable 3-manifold constructed as a $T^2$-bundle over $S^1$ with orientation-reversing monodromy represented on $H^1(T^2;\mathbb Z/2)$ by the matrix $\begin{pmatrix}1&1\\1&0\end{pmatrix}$ admits stably exotic fillings for some normal 1-type data.

Background

The paper constructs a nonorientable T2T^2-bundle over S1S^1 whose monodromy has no nonzero fixed points on H1(T2;Z/2)H^1(T^2;\mathbb Z/2). Consequently, every tangential Pin+^+ structure induces the same non-bounding spin structure on the fibre, so the manifold does not Pin+^+-bound and the sufficient criterion used earlier cannot establish stably exotic fillings. The authors leave open whether stably exotic fillings might nevertheless exist using a different normal 1-type.

References

We do not know whether this $Y$ admits stably exotic fillings, for some other normal 1-type data.

Stably exotic fillings of 3-manifolds  (2608.23523 - Kasprowski et al., 24 Aug 2026) in Example 4.4, Section 4 (Examples)