unable to set up the networks

[Nkorchi]

• OS: Ubuntu 18.04
• BigchainDB version: 2.2.1
  I have four VMs, each running BigchainDB and MongoDB inside a Docker container and a Tendermint installation in the VM. I am trying to connect the four instances. When running tendermint node, I get several errors that look like this:

E[2022-08-07|22:00:29.410] Dialing failed module=pex addr=4c9fa2f3c6620c1b96ed2ddfb004b977736f8f76@152.7.177.221:26656 err="dial tcp 152.7.177.221:26656: connect: no route to host" attempts=0
When all three of the services (Mongo, Bigchain, Tendermint) are containerized, it does work once I introduce port forwarding, but as-is (which is my specific use case), the nodes cannot seem to find each other. From this question's reply, I made sure BigchainDB is listening (inside the container) using lsof -i :26658, and this port is forwarded. Following this question's answer, I also tried using the persistent_peers setting, but that doesn't seem to do it either.

How do I connect these VMs?