Welcome to LCL sherikoska!
I understand your frustration, it does take some time to get used to how everything works on a Newell , it can be a real learning curve!! I would try and have your wiring issue fixed, if it is just some loose wires it may cause more "gremlins" later on down the road. It sounds like someone my have been up under the dash and bumped some wires. Grounds are a good thing to check also, they can be troublesome. With your wiper motor it could be your switch, fuse, loose wire or ground. If the shop you had look at it doesnt seem compitent it would be a good idea to get someone that knows how to troubleshoot wiring check it over.
Upgrading your back-up cam to a gps system would be nice rather than a replacement camara but I would still look in to your wiring issue, sometimes its as easy as a loose connecter or ground, just a matter of finding it
