Zelmanov's strongness conjecture for Engel Lie algebras

Let $n$ and $p$ be integers with $n<p$, and let $L$ be an $n$-Engel Lie algebra over $\mathbb{F}_p$. For every $x e L$, let $I(x)$ be the ideal generated by $x$; call $L$ $k$-strong if $I(x)^k=0$ for every $x e L$. Zelmanov's conjecture. There is some $k$ such that $L$ is $k$-strong. The conjecture would exclude examples of $n$-Engel Lie algebras that are not $k$-strong when $n<p$, and would support the reduction of the Wilson conjecture to the study of \omega-categorical $k$-strong Lie algebras. Its resolution status is not specified in the source.