You can still get the Minecraft Anniversary Cape

Summary:
You can still get the Minecraft Anniversary Cape. To do this, you need to open Minecraft using the link.

Steps to reproduce:

1. Switch to an account that does not own the Minecraft Anniversary Cape.
2. Open minecraft via the link https://open.marketplacebot.net/dressingroomoffer/7118a7d5-240e-4f6d-8959-5269ba041938
3. If you don't see Minecraft Anniversary Cape - open the tab with capes and return to the main screen, then reopen Minecraft using the link.
4. Click on the "Get" button.

Observed results:
You've received the Minecraft Anniversary Cape!

Expected results:
The Minecraft Anniversary Cape can no longer be obtained.

Video:
The author in the video also advises to contact support to get Minecraft Anniversary Cape in Java.
https://youtu.be/_MQ0hxnQzKM