Definitely feasible, although CPR is done via the sternum, in the centre of the front chest wall. And ribs may be fractured with vigorous resuscitation, and they tend to crack further out towards the sides.
And may be one line that the defence may follow... I'm not sure they'd proceed with the suicide line of defence, given what even we amateurs have found so far about Zoloft, post-mortem redistribution, and liver concentrations, etc.
Are you thinking a possible negligent manslaughter defence? Along with the interfering with the corpse bit? Or however the legalese goes?
Just a whisker over two months before the committal hearing - but who is counting? :waitasec: