Ok. It is extremely likely that your foggy night image is due to IR light bleeding inside the camera as I described earlier. If the IR is getting in through the front of the lens then there is little you can do besides using 3rd party IR illumination, but this assumes you can disable the IR LEDs on the camera and still have the mechanical IR filter functioning normally. However if the IR is getting in through gaps near the image sensor or IR filter, then you should be able to solve it by wrapping the area with black electrical tape as this will stop IR from bleeding in. Inside the camera, you will likely find the imaging sensor just a few millimeters behind the lens, with a small mechanical IR filter between them (this may have its own wire, making it easy to identify). If there is any possibility that scattered IR inside the camera enclosure is making it through a gap in this area, it could be the source of the IR bleed.
If you decide you need a different camera, the Hikvision is a really good choice. Yeah, I know you'd prefer one with WiFi but I think you'll find that all the really high quality cameras only ever have WiFi on their indoor models. Ideally you would run shielded ethernet from inside your house but if that is not possible you can try Powerline networking gear from Amazon. Pricing varies... I tried this one
http://smile.amazon.com/dp/B006L6X7PM which is about $50 for the complete kit. I installed my powerline wall warts on separate circuits at opposite ends of the house and got about 40 Mbps throughput. Kind of crummy for something that advertises 500 Mbps, but it has been rock solid for over a month. Another alternative would be a a wifi adapter that you could use to connect the camera to your home network. An Ubiquiti Nanostation Loco M2
with its power output set to the minimum would do the job nicely, assuming you have a sheltered place to make the power and ethernet connections for it.