The decays \( B\to {\overline{D}}^{\left(\ast \right)}\omega \pi \) are very important for the investigation of ρ excitations and the test of factorization hypothesis for B meson decays. The \( {B}^{+}\to {\overline{D}}^{\left(\ast \right)0}\omega {\pi}^{+} \) and B0 → D(*)−ωπ+ have been measured by different collaborations but without any predictions for their observables on theoretical side. In this work, we study the contributions of ρ(770, 1450) → ωπ for the cascade decays \( {B}^{+}\to {\overline{D}}^{\left(\ast \right)0}{\rho}^{+}\to {\overline{D}}^{\left(\ast \right)0}\omega {\pi}^{+} \) , B0 → D(*)−ρ+ → D(*)−ωπ+ and \( {B}_s^0\to {D}_s^{\left(\ast \right)-}{\rho}^{+}\to {D}^{\left(\ast \right)-}\omega {\pi}^{+} \) . We introduce ρ(770, 1450) → ωπ subprocesses into the distribution amplitudes for ωπ system via the vector form factor Fωπ(s) and then predict the branching fractions for the first time for concerned quasi-two-body decays with ρ(770, 1450) → ωπ, as well as the corresponding longitudinal polarization fractions ΓL/Γ for the cases with the vector \( {\overline{D}}^{\ast 0} \) or \( {D}_{(s)}^{\ast -} \) in their final states. The branching fractions of these quasi-two-body decays are predicted at the order of 10−3, which can be detected at the LHCb and Belle-II experiments. The predictions for the decays B0 → D*−ρ(770)+ → D*−ωπ+ and B0 → D*−ρ(1450)+ → D*−ωπ+ agree well with the measurements from Belle Collaboration. In order to avoid the pollution from annihilation Feynman diagrams, we recommend to take the \( {B}_s^0\to {D}_s^{\ast -}\rho {\left(770,1450\right)}^{+} \) decays, which have only emission diagrams at quark level, to test the factorization hypothesis for B decays.
