Visit Johnny or Heidi in cat-town who mention they got stuck with crappy chairs. If you are willing to collect pristine gorilla parts for one of them to make a new chair, they will offer to call Jade the bank for you. Jade seems to spend most of her time at the cheese wheel, she has turned bankers hours into almost nothing!
Collect 1 pristine gorilla canine, 1 pristine gorilla pelt, and 2 pristine gorilla paws. Once turned in, you will be flagged for Stonebrunt bank access. You can check on your character page to see your flags.
Big thanks to Spock for his endless dedication and hard work collecting materials for Bubar to open the bank!