Broken screen, no wifi. How odd.

Customer's iPhone 5s was dropped, screen smashed but functional. Customer's boyfriend replaced the screen with one he bought from ebay. Upon reassembly they discovered that the touch function on the button no longer worked, and the phone was no longer able to get on wifi (Settings -> Wifi was grayed out, as was the icon in the Control Center). Following directions he found online, he reset the network settings (Settings -> General -> Reset -> Reset Network Settings). When the iPhone rebooted Settings -> Wifi was now accessible, but when he tapped on it the phone would hang; the Settings app basically crashed. After some more experimentation he reset the iPhone completely (Settings -> General -> Reset -> Erase All Content and Settings). When the phone rebooted/reset Wifi remained accessible and he can tap on it without crashing the phone, but no wifi networks show up. It just pinwheels, looking for networks, but finds nothing.

That's how the phone is now. The touch button part is probably just clumsiness; he probably damaged it when moving it from the old display to the new. But the wifi thing is a question mark to me. It's odd to me that it would behave differently during the various resets. Replace the wifi antenna?