Neumann's strong conjecture on Bloch groups of number fields

Let $F\subset\mathbb C$ be a concrete number field which is not contained in $\mathbb R$. Let $\mathcal B(F)$ be the Bloch group of $F$, and call a hyperbolic $3$-manifold admissible over $F$ when its invariant trace field is contained in $F$. Neumann's strong conjecture. The Bloch group $\mathcal B(F)$ is generated integrally modulo torsion by admissible hyperbolic $3$-manifolds. The conjecture refines generation over $\mathbb C$ to each non-real concrete number field; the source gives no resolution.