Docker host not passing return traffic to containers

Hello all,

Running on a RHEL8 x86_64 server with docker-CE v26.1.3

I have 4 containers that need to make connections outside the local docker host. If I attempt to run a curl or wget from inside one of these containers to reach an outside server, a tcpdump on the remote server will show that the session is established with the normal 3-way handshake, but after that the remote server attempts to send its response packets and while they arrive at the docker host, they are never forwarded on to the container. So the remote server just continues to retransmit the packet until it gives up and the session times out.

I have these containers working on a PhotonOS server just fine and the configuration was copied directly from there. If I look at the iptables for the nat config, that all looks the same between the photon and RHEL docker hosts. What should I be looking at?