Nice setup, thanks for sharing. And I'm glad Tina is getting better, she's very pretty.
I'm not surprised you heard 2 weeks since nothing is cast in concrete. One rule of thumb says 30 days & 30 feet away from any other birds. Another common "rule" is 3 weeks. And I'm sure a lot of people give up at 2 weeks. One reason for longer times is that stress from adjusting to a new environment can weaken their immune system and that "bug" they were previously fighting off might now wins the war. Also the "bugs" on your property are likely different than where the new bird came from. She will have built up an immunity to the bugs in her former location but now she's faced with new strains. (think of traveling to Mexico) The 30 days gives her time to level out, develop any issues that are borderline or new, and then show you the symptoms so you can treat as needed. All animals, by instinct, are going to hide symptoms of sickness as much as possible.
I'm assuming you're treating for internal and external pests twice, the second dose being 10 days after the first.
BTW... that's a very interesting feeder. I haven't seen that design before. Do they have any issues with sticking their head inside to eat? Love the "stairs", too!