We see all our other search peers, but we don't see the two new indexers stats. I've doubled check and the two new indexers are search peers to each search head in the cluster and are also search peers to the deployment server as well.
Just because you added them as search peers does not mean that you added them as forwarder destinations! Did you update your outputs.conf
files that are deployed to your forwarders and then restart the splunk instances there?