Hey TBT water,
The PBE client is different than the NA (live) client, which is why you needed to install a completely different client for PBE.
When you installed, did you follow the instructions in the FAQ?
For Windows:
- Download the Windows PBE client here
- Open "PBE_Client_Shell.zip"
- Copy and paste the entire PBE folder anywhere on your PC except the directory you're using for your main League of Legends installation. Hosting the PBE files and the main League of Legends files in the same directory has been reported to cause problems.
- Double click on "lol.launcher.exe" or "lol.launcher.admin.exe" to run the launcher and start patching.
When you installed the PBE client, did you install it in a different directory than your live (NA) client?
You're correct that your NA account isn't compatible with PBE and visa versa. You'll need to make a PBE account.