Ok, after 2 weeks of troubleshooting, this is what I know and what I don't know. Cut to the chase - in order for an iPhone to work, you need a 2.1 HDMI cable with male HDMI and male USB-C - Amazon - Cable Matters USB C to HDMI 2.1 Cable 3 ft, Support 4K@240Hz and 8K@60Hz, HDR - Thunderbolt 4, Thunderbolt 5, USB 4 Compatible with MacBook Pro, XPS, ThinkPad - Max Resolution on macOS is 4K 60Hz. Do NOT use the 2.0. You might get sound, but you will NOT get a picture.
My bluetooth headphones work well.
I have a jail broken Firestick. I can watch everything on my firestick, either on the passenger screen or the main screen - even when driving. I order to use the Firestick, I need two additional connectors due to the face the power source for the firestick is on top and too close to the bottom of the radio. So to get power to the Firestick, I bought - CableCreation Short Micro USB to USB C Cable 0.65 FT, Braided USBC to MicroUSB OTG 480Mbps Cord for Wall Chargers, MacBook Pro, Air, Galaxy S22, S21, Pixel 5/4/3 & More, 0.2M Space Gray. For the HDMI port, I bought this - Highwings 8K HDMI Extender Cable, Utra High Speed HDMI 2.1 Adapter for 4K@30/60/120Hz, Compatible with Xbox PS5 PS4 Roku TV Laptop PC, 1FT. This piece gives me the clearance to plug in the power source.
Now the part what I do NOT know. How to use my Pixel 6 Pro using HDMI. Regardless of the cable I am using, when I plug it in, my phone asks me why I am using the connection for. It will stay on charging, but when I attempt to switch it, I receive an error - cannot connect - and defaults back to charging. The issue is not the truck, but with my phone.
So to summarize - Apple devices will connect to the passenger screen only using the HDMI 2.1 cable. Firesticks will work, but you will like need an extender and cable for power. Google phones - well, still trying to figure it out.