He came to City because it is his dream to play in Europe and especially in PL.
The problem is that the training period was short (only 2 weeks) and when he joined City, the first team had already finished all friendly matches and thus Omar Abdel-Rahman was given the option to play with the youth team.
So I think he did not get a real opportunity to show his real talent. I think also the talks about the inability for him to join City directly due to the national team ranking is another reason for him to reject to be sent to a small team in a small league. Omar has great confidence in himself, and he is working hard to develop himself and therefore he thinks hat he tdeserve to play for a big team