Chalupnik's formality conjecture for derived Frobenius twists

Let $k$ be a field of characteristic $p$, let $r$ be a nonnegative integer, and let $G$ belong to the category of homogeneous strict polynomial functors of degree $d$. Let $G^{(r)}$ denote its $r$-th Frobenius twist, let $\boldsymbol{K}^{\boldsymbol r}$ be the relevant derived functor, and let $E_r$ be the graded vector space of dimension $p^r$ that is equal to $k$ in dimensions $2i$ for $0\leq i<p^r$ and zero otherwise. Chalupnik's formality conjecture.

$$\boldsymbol{K}^{\boldsymbol r}(G^{(r)})\cong G_{E_r}$$

in the bounded derived category of strict polynomial functors. In particular, $\boldsymbol{K}^{\boldsymbol r}(G^{(r)})$ is formal. The source does not provide evidence resolving this conjecture, so its status remains open.