Nebbia's CCR conjecture for boundary-transitive groups on semi-regular trees

Let $T$ be a thick semi-regular tree, and let $G$ be a closed subgroup of $\operatorname{Aut}(T)$ acting transitively on the boundary $\partial T$. A locally compact group $G$ is CCR if $\pi(f)$ is compact for every irreducible representation $\pi$ of $G$ and every $f\in L^1(G)$. Nebbia's conjecture. Every such group $G$ is CCR.

The conjecture proposes that sufficiently regular boundary action forces regularity of the unitary dual. Earlier results establish implications from CCR or Type I assumptions to boundary transitivity, while the converse remains open in this generality.