[step:Recover the weighted Ricci tensor lower bound from $BE(K,N)$]
Assume $BE(K,N)$. Fix $p\in M$ and $X\in T_pM$. Let $A:T_pM\times T_pM\to\mathbb R$ be any symmetric bilinear form. By the compactly supported jet-realization lemma in a smooth manifold, there exists $f\in C_c^\infty(M)$ such that
\begin{align*}
\nabla f(p)=X
\end{align*}
and
\begin{align*}
\nabla^2f(p)=A.
\end{align*}
This lemma follows by taking normal coordinates on a relatively compact coordinate ball around $p$, prescribing the degree-two Taylor polynomial there, and multiplying by a smooth cutoff equal to $1$ near $p$.
For $N=\infty$, choose $A=0$. The Bochner identity and $BE(K,\infty)$ give
\begin{align*}
\operatorname{Ric}_{V,\infty}(X,X)=\Gamma_2(f)(p)\ge K\Gamma(f)(p)=K|X|^2.
\end{align*}
Since $p$ and $X$ were arbitrary, $\operatorname{Ric}_{V,\infty}\ge Kg$.
Let $N\in(n,\infty)$. Define
\begin{align*}
b:=g_p(\nabla V(p),X).
\end{align*}
For each $a\in\mathbb R$, choose $A_a:T_pM\times T_pM\to\mathbb R$ to be
\begin{align*}
A_a:=\frac{a}{n}\,g_p.
\end{align*}
Then $\operatorname{tr}_{g_p}A_a=a$ and $|A_a|_{\mathrm{HS}}^2=a^2/n$. Applying $BE(K,N)$ to a compactly supported function with $\nabla f(p)=X$ and $\nabla^2f(p)=A_a$ gives
\begin{align*}
\frac{a^2}{n}+\operatorname{Ric}_{V,\infty}(X,X)\ge K|X|^2+\frac{(a-b)^2}{N}.
\end{align*}
Rearranging,
\begin{align*}
\operatorname{Ric}_{V,\infty}(X,X)-K|X|^2\ge \frac{(a-b)^2}{N}-\frac{a^2}{n}.
\end{align*}
The right-hand side is maximized over $a\in\mathbb R$ at
\begin{align*}
a=-\frac{nb}{N-n},
\end{align*}
and the maximum value is
\begin{align*}
\frac{b^2}{N-n}.
\end{align*}
Therefore
\begin{align*}
\operatorname{Ric}_{V,\infty}(X,X)-K|X|^2\ge \frac{b^2}{N-n}.
\end{align*}
Equivalently,
\begin{align*}
\operatorname{Ric}_{V,N}(X,X)\ge K|X|^2.
\end{align*}
Since $p\in M$ and $X\in T_pM$ were arbitrary, $\operatorname{Ric}_{V,N}\ge Kg$.
[/step]