I think I also have a faulty charging port, only the wireless charging is working now, when I plug into any usb there is the lightning icon but it says not charging. I'll switch the daughter board with the one from my other broken nexus 4 to see if it fix the issue.
As much as I like my Nexus 4, I'm not impressed by reliability. In under 2 year, I've had 2 broken screen, 1 broken bake cover, 1 expanded battery and now possibly the charging port. My nexus S and Galaxy nexus with a million drop each are still working as new