According to Itohan:

"By default, when istio is installed, it only allows forwarding traffic to services in the remote cluster with the "global" suffix. In order to enable istio to forward traffic, we need to change the suffix in some of its resources. Get the following istio resources and edit them (kubectl edit <resource-type> <resource-name> -n <resource-namespace>), change all occurences of the global suffix in each of these resources to your custom suffix.

1. Add lc1 stubdomain in kube-system coredns cm
2. Change istio coredns cm to new suffix
3. Edit envoyfilter to use customsuffix
4. Edit istio ingressgateway to use custom suffix
5. Edit istio destination rule to use custom suffix
6. Make sure service entry uses the right suffix

Note: I have only tested using one custom suffix (e.g) lc1 at a time, I have not tested adding multiple custom suffixes."

I will test this and provide results/conclusions here.