In this paper we study conditions under which, for an inclusion of finite von Neumann algebras $N \subseteq M$, we have the reduced amalgamated free product $\ast_N M$ is embeddable into $(R \bar{\otimes} N_1)^\omega$ for some other finite von Neumann algebra $N_1$, where $R$ is the hyperfinite $\textrm{II}_1$ factor.
Comment: Main text by Weichen Gao. Appendix by Marius Junge and Weichen Gao. This is a revised version of the original paper containing more recent results and a new appendix by Marius Junge and Weichen Gao