Issue adding new nodes to existing cluster

[Tyler Hawkes]

When trying to add new nodes to an existing cluster, the next button on
step 3 (endpoint is /#/main/host/add/step3) is disabled. Any ideas why?
I've tried restarting the server. None of the the configurations are out of
date and none of the checks that are alerting on the previous step are
significant since all the other nodes in my cluster installed with them.