Wow! hahaha, that's what it was ... oh my, I feel smart. Yeah, using 0's and 0's probably wasn't the best idea in my test lab.

Thank you!

Even though that did work, I'm still missing something. When I connect to the listener with ;ApplicationIntent=ReadOnly, it still lands on the current primary (which is SQL01\AO1):

Shouldn't I have landed on SQL03 first?

ALTER AVAILABILITY GROUP [AG4] MODIFY REPLICA ON N'SQL01\AO1' WITH (PRIMARY_ROLE (READ_ONLY_ROUTING_LIST = ('SQL03\AO3','SQL02\AO2','SQL01\AO1')));