Costel deserves to play in the final as that's been the deal all season. Whether he's leaving or not. If he is, then he will make sure that he plays to the best of his ability. His attitude has never been anything other than 100% commitment to the club, despite his limited opportunities.
Like a lot of foreign players though, he is truly dedicated to his country and if leaving and playing regularly will put him back as Romania's number one, then it's something he has to do.
On a personal level I can say that he is a perfect gentleman off the pitch and never refuses an autograph. I have one of his old Timisoara shirts and when he saw it and confirmed it was his, he signed a little message in Romanian (probably said ""You're a knob", but who cares!) I also got him to sign one of his Europa league shirts and he did the same thing as he knew me from the other time. Really nice bloke and if I still lived near enough to Carrington to see him before he leaves, I would. Unfortunately I won't get the chance!
To be fair, Joe Hart is the same and despite being England's number one, he will always sign for the fans too. I've known occasions when he hasn't been able to stop for genuine reasons and you can tell he feels really guilty about not being able to stop. Actually most of City's players are very good like that, especially the English ones. Occasionally Sergio and Yaya won't stop and Tevez is a bit hit and miss, but apart from that, most players are an absolute credit to the club. The one exception though is Nasri, who never ever ever ever ever stops. Nasri is all that's wrong with today's players. Up his own arse and extremely ignorant. To paraphrase from another thread, Nasri is the skidmark on City's underpants. Ignorant bastard he is. I wouldn't mind if he did the business on the pitch but he doesn't even do that for the most part. And if he was player of the month in April, then it was a bloody long time coming, and I suspect that it will be the one and only time that twat wins it.