Best practices for a 2-node Patroni + PostgreSQL cluster with a external/witness DCS

Hello PostgreSQL Community,

I am planning to set up a high-availability PostgreSQL cluster using
Patroni. Due to infrastructure constraints, I only have two dedicated
database nodes available.
I know that a Distributed Configuration Store (like etcd or Consul)
requires an odd number of nodes (minimum 3) to achieve quorum and safely
prevent split-brain scenarios.

Before I begin the deployment, I would appreciate your advice on the
following architectural approaches:
1. Is it recommended to run a 3-node etcd cluster where 2 instances live
on the DB nodes and a 3rd "witness" instance lives on a lightweight
application server/VM?
2. Alternatively, does Patroni safely support a 2-node setup using a single
external DCS instance, or does that introduce a critical single point of
failure (SPOF)?

Any architectural pointers or template configurations for this constraint
would be highly appreciated.
Thanks!