i havent use wizzair, but i travel last month to asia with all my nitro racing stuff(lipo battery,diff&shock oils and parts) and put all of them inside my luggage and i never had a problem. i flew from heathrow 4.
you sould be ok with your RC. just dont bring fuel or even that nitro blaster or those kind of stuff that is a big NO in the plane. the only thing that your going to have problem is, if your using lipo or life to power up your nitro car. coz some of airline wont let you to bring it. im not sure about mine when i put all my RC stuff in my bag or maybe im just lucky that day. but if your using nimh battery that sould be ok just put tape on connector.
hope this will help you