@Shadowgate1 First, you need to select realm of delivery. That is where the bundle will be delivered to.
If you want bundle on S8 Thrall then https://ascension.gg/store/thrall/514/ascension-wrath-of-the-lich-king-alpha-bundle/ascension-bundles
If you preffer it on Area 52 instead then https://ascension.gg/store/area-52/514/ascension-wrath-of-the-lich-king-alpha-bundle/ascension-bundles
Once you have the item in cart, you need to select character for delivery. Once you purchase the bundle, head to that realm and character -> mailbox.
Use the Travel Guide item inside of the bundle.
Once you do that, please close the game and open your Ascension launcher. Now, you should have "PTR" dropdown above the play button of the launcher. Select that and let it download PTR client.
After the client is installed, you should be able to select Grizzly hills on realm selection.