engine cover and oil filler self removal

Gone to fill the washer fluid up in my vRS and noticed the top part of the oil filler cap to have dissapeared, the threaded lower part is still in the top of the engine, at which point I also discovered the engine top cover was completely loose and has being rubbing on the back of the bonnet

any idea what's caused this? dodgy engine mount? needless to say its going to the main stealer's