Its possible your internal adapter is not going to work under Linux, this happens more often then you think when hardware is only made for Windows, as no drivers were made or released for Linux users.
However, one thing you can try, is install Blueman Bluetooth Manager from the Software Store. Its from the Blueman group, youll see that on the page, to know you selected the right one.
Install that, and see if you can turn the adapter on with Blueman. You will probably have to restart, Blueman will let you know. If Blueman can't activate your wireless adapter, then nothing can in Linux.
If this is the end result, then us, you will have to rely on the wireless USB dongle in the end.
