The AWS Load Balancer operator by default doesn't use the OpenShift generated trusted ca-bundle. It needs to be done manually as per the following link.
--> https://github.com/openshift/aws-load-balancer-operator/blob/b757416f27d3a84113b4660358b98cca0064731f/docs/proxy.md 

As the CA bundle is generated by OpenShift itself, the operator should be using it by default. The customer already raised the PR for it.

--> https://github.com/openshift/aws-load-balancer-operator/pull/129