I'd be very surprised if the new manager adopted a 4-4-2. I think the most that might happen, if results were iffy, is a change away from a back three towards a 4-2-3-1 or a 4-3-3.

Regarding Kyle Cameron, I think he's a good footballer but not a natural defender, so I'm not sure he would be any stronger at left-back than at centre-half. He does indeed lose concentration too often, and he sees danger far too late, which is why he has to use panic measures or claiming fake fouls to get himself out of trouble. I think his long-term future could be as a midfielder as long as he's willing to put in the shift required, because his ability as a passer isn't in doubt, and being in the hurly-burly of the centre of the park might help him focus more.