> And I still can't figure out why a freshly wiped unlocked phone w/ a Sprint SIM is running a Verizon provisioning process.
Samsung has a rather "interesting" (to say the least) firmware development process (if you can call it a process). It seems that most handsets certainly used to ship with if-gated Verizon specific hacks all over the firmwares, regardless of market the device was for. I believe this was just for simplicity's sake. It sounds like nothing has changed there.
As much as Samsung loves to advertise enterprise security like Knox, it only takes a few minutes of digging through the history of Knox to see some blunders from the early days, like storing the plaintext Knox PIN, to really wonder how on earth they can secure it.
Call me old fashioned, but I just don't have any confidence in the development practices of any phone vendor these days - even plain pure AOSP Android has so many external library dependencies, each of which is receiving CVEs and patches regularly (hopefully), and needs to be kept updated by AOSP maintainers.
I used to track the ancient kernel CVEs that were being rediscovered in Android due to poor or non existent source code control in OEM kernels. I gave up as it was pretty much a flood of 2 or 3 year old bugs being rediscovered as unlatched on Android or Qualcomm kernels.