Default Bluetooth Tethering Doesn't Work

I've converted my AT&T HTC One M8 to a GPe by using the RUU flash method. Everything seems to work perfectly.

Except bluetooth tethering, which is the main reason I did the conversion in the first place. I can turn on bluetooth tethering. I can pair up with my older HTC One M7 (also an AT&T device converted to a GPe), and they hook up to each other just fine. My M8 states it's sharing its internet connection. My M7 states it's using the M8's Internet connection via bluetooth. But when I try to do anything Internet-related with my M7, nothing works, and it says I'm not online (even though the tethering icon is lit up right there in the status bar).

I have no idea what's wrong.