Broken iPhone - eviltoast

I recently slipped over with my iPhone 12 in my back pocket I also happened to have my keys in the same pocket. As I fell over my entire body weight fell on my phone and the keys pierced the back of the phone pushing through and cracking the front glass. The phone works the screen still works same with Face ID and all the cameras. The only thing that doesn’t work. My Friend used to have a phone repair shop. He’s replaced the front and back glass and all the inner parts seem to be perfectly fine. However it won’t connect to any networks what so every no Cellular No Wi-Fi no Bluetooth. He thinks it’s the logic board inside could it be anything simpler or is it gonna cost me a bomb?