External IPs on OCP4 are not routable

Running OCP4 on vSphere, I can not get external IPs to work. I have tried both spec.externalIP.autoAssignCIDRs and MetalLB. The assigned external IPs are accessible from nodes within the cluster (with curl), but routing from an external system fails. I have tried manually adding routes for the external IP range on the RHCOS nodes, but it doesn't work. Any externally routed packet just gets sent to the default router. I have tried manual static routes on the RHCOS nodes to route the external subnet to a master node or worker nodes and that doesn't work. I can assume this is an iptables issue but there is no documentation on how to configure it. I know I am not the only one to have this issue as I have found multiple posts asking for help with this very same problem, but there is never a reply with a solution.