I have supported friends through removal of jurisdiction battles and not a single one was successful. Of all the cases I have seen, your DD’s is the one with less merit by FAR.
No court would agree for the child to be removed from the country when the dad is in regular contact, much less so, given Dubai’s record and distance to father. The court will see rightly that this is not done on the girl’s best interests but her mother’s. Having a good job elsewhere is not grounds for allowing the change, as it could be easily argued that if she can get such a nice job there, she can surely find another in the UK without ending up living under a bridge.
The other thing your DD needs to consider is that family courts move at snail’s pace, they are not going to decide in a few weeks to allow the removal of a child, we are talking years here (and many £10,000s in legal fees) so no new employer will wait that long.
A removal of jurisdiction process will kill any good will left between the parents which is, incidentally, what the child needs to have stability while growing up. It will also throw the child into a series of long, painful and unfortunate prodding as each parent fights their corner trying to prove the other parent is not such a fit parent so the court agrees or disagrees with the removal. I wouldn’t put my child or myself through that just for a nice job under the sun and a possibly better school, and that goes without saying that the chances of winning are very, very slim.