I have figured out how to enable the HTC to share it's internet via bluetooth:
Mobile Network Sharing -> Bluetooth Tethering [checked on]
But I am unable to find a way to allow the Droid 3 to consume the internet via bluetooth. I can get the Droid 3 to broadcast using 3rd part apps, btu can't figure out how to consume.
Note, this Droid 3 is my old phone that I am still using in my car as I can't mount my HTC One for non-technical reasons.
This looks like a duplicate of another reverse tethering issue which is a duplicate itself, but the answer listed can't be found.