I'm really struggling with your logic here. Mbokane has a pretty good scoring record at 3 clubs, less so at two others. He also averages a goal every two games at international level. His "bad attitude" is based on being unhappy about Rebrov mechanically rotating his squad, even when someone's just had blinder.
RvW has bombed in English and French football, and, by your apparent definition also has a "bad attitude" having slated Norwich in the French press and allowed his agent to state that the Championship wasn't "an appropriate stage " for him. "Talented strikers" score even in unsuitable systems, which is why they go for big money. Ricky is a limited finisher who seems to need a system built around him but isn't good enough to justify it. As I've said before, he's a nice lad and I'd have loved him to succeed but he simply hasn't, however many excuses are made for him.
Mbokani has a good scoring record in generally poorer leagues (since when did anyone rave about the Belgian or Ukrainian leagues???), but in both Germany and France he failed miserably, in fact his record at Monaco was worse than RvW's at St.Etienne despite him having much better players around him than RvW did (and people have already slated RvW's scoring record for St.Etienne, so what does that say about Mbokani???)
In regards to his International scoring record, the majority of his goals are against fellow ACON countries like Ghana, Congo and similar, which with respect are hardly heavyweights of football, and certainly not compared to the sides that a European or even South American based international would have to face in the Euro's or World Cup.
RvW 'bombed' for us last time based on Hughton playing in a completely different role than which he's suited combined with a complete lack of decent supply in the process, much like how Henry had a poor scoring record for Juve due him being played on the wing (being fair, he was seen as a winger at the time) but when Wenger played him upfront the picture changed and a legend began. This is similar IMHO, you cannot sign a player like RvW who relies on clever through balls or balls across the 6yrd box and then insist on him playing as a strong target man who needs to hold the ball up! Christ, even Holt lost 50% of his goals under Hughton, yet apparently it's all RvW's fault that he struggled to perform whilst players like Holt get off scot free...
As for 'bad attitude', generally speaking he's shown good regard for our club, our city and our fans, he clearly has an issue with Hughton (and I don't f**king blame him) who in truth has probably destroyed his career unless something changes sharpish and he's also shown a good response to AN and has worked hard and looked good in pre-season (even if the goals haven't come), whereas from what I understand, Mbokani has had issues at pretty much EVERY club he's played at and hasn't been afraid to say so, and based on this I know which of the two attitudes I'd take.
Unless you're talking about world class, 'complete' strikers e.g. Van Persie or Ibrahimovic, then a striker needs good support and supply from his teammates, something which I don't think any Norwich fan can genuinely say RvW received that season. RvW DOES need more of a system around him to play to his strengths, but we should have known this from day one (it's not like his style of play changed that much during his years at Utrecht and Lisbon), and if Hughton wanted a big target man, then he should have damn well signed one, instead of getting a goal poacher who likes to play on the shoulder of the defender and then wondering why it's not working...
There HAS to be some accountability from RvW for his lack of goals and sometimes lukewarm to poor performances, but by the time we got to the infamous 'Ghost Pass', he'd already had his confidence shot to ribbons and was completely demoralized by the whole sorry situation.
Chances are that he'll be moved on in the next month, but if we do keep him, I really do hope that AN used him in the right way, and doesn't expect him to come on for CJ and offer the same to the team because it just won't happen, and it STILL wouldn't be RvW's fault if that was the case.