  Let $ G $ be a countable discrete group and consider a nonsingular Bernoulli
shift action $ G \curvearrowright \prod_{g\in G }(\{0,1\},\mu_g)$ with two base
points. When $ G $ is exact, under a certain finiteness assumption on the
measures $\{\mu_g\}_{g\in G }$, we construct a boundary for the Bernoulli
crossed product C$^*$-algebra that admits some commutativity and amenability in
the sense of Ozawa's bi-exactness. As a consequence, we obtain that any such
Bernoulli action is solid. This generalizes solidity of measure preserving
Bernoulli actions by Ozawa and Chifan--Ioana, and is the first rigidity result
in the non measure preserving case. For the proof, we use anti-symmetric Fock
spaces and left creation operators to construct the boundary and therefore the
assumption of having two base points is crucial.
