I’m not sure I understand what you mean by “namespaced ingress controller.” You may be able to configure the ingress class for Kong. If that doesn’t make sense you can change the ingress class used by all Okteto generated dev ingress using some configuration if you are hosting your own instance, Configuration Settings | Okteto Documentation. This may affect too many ingress for you though? Also, you’d lose some of Okteto’s auto-ingress functionality if using Kong.
Does How can I run traefik on an okteto namespace? possibly help?