Pappas's corrected local model flatness conjecture for orthogonal groups

Let $F$ be a field with discriminant algebra $A=F\oplus\mathcal D$, let $V$ be the associated quadratic space of dimension $2n$, and let $M$ be the corrected local model obtained from the naive local model after base change to the integral closure $\mathcal O_A$ and imposing

$$\wedge^n(\mathcal F_\Lambda)\subset (\wedge^n\Lambda_{\mathcal O_A})_+\otimes_{\mathcal O_A}\mathcal O_S.$$

The scheme $M$ is regarded as an $\mathcal O_F$-scheme via its structural morphism.

Corrected local model flatness conjecture. The scheme $M$ is flat over

$$\operatorname{Spec}(\mathcal O_F).$$

The correction is designed to repair the non-flatness of naive local models while preserving the generic fiber. The source proposes this flatness as a conjecture and gives no resolution in the supplied text.