So, after the dealership, we might be able to help you in at least isolating it between the "normal' bluetooth connection, and the Carplay application.
Your statement: BUT I CAN'T GET THE PHONE TO SHOW UP IN MUSIC, MAPS OR CONTACTS WITHOUT A USB CONNECTION PLUGGED IN
does not make sense, the phone does not show up in a music app, the tunes on the phone should show.. you seem to imply that it works with a usb cable, so perhaps it is a setting.
On my '24 prime, (I have android) , you ENABLE the normal "phone type" apps via Bluetooth SEPARATELY from the Android Auto app (but in your case Carplay)... this could be your problem
Greg