Peng–Zhao's clique conjecture for dense uniform hypergraphs

Let $t$, $m$, and $r\geq 3$ be positive integers satisfying

$${t-1 \choose r} \leq m \leq {t-1 \choose r}+{t-2 \choose r-1}.$$

Let $G$ be an $r$-graph with $m$ edges that contains a clique of order $t-1$.

Peng–Zhao's conjecture. The Lagrangian of $G$ satisfies

$$\lambda(G)=\lambda([t-1]^{(r)}).$$

This conjecture concerns the extremal Lagrangian of an $r$-uniform hypergraph in the range where its number of edges is between that of the complete $r$-graph on $t-1$ vertices and that quantity plus ${t-2 \choose r-1}$. The supplied text attributes the conjecture to Peng and Zhao, but gives no evidence of a resolution, so its status is left open.