Yep, that was it. Got it working now. Thanks a lot!
FYI for anyone else with this issue who has no idea what the heck permissive mode is or how to change it (like me), there is an app for rooted androids called SELinuxModeChanger that lets you switch your device between "Permissive" and "Enforcing" mode easily with one touch. I DL'd the app, made the change to permissive, made sure the appradio connections were correct and then began the appradio startup process again. It didn't work the first time, so I rebooted my phone while still plugged in. When it rebooted, it worked!