The idea is "sound" ...
Remember, she's already outside the Philippines, so doesn't have to convince the British Embassy in Manila that she'll "disappear", or an economic refugee!
If she wanted to disappear into the black economy of the Gulf States she'd have done that long ago.
But as you,ve stated, she's always complied with the immigration laws.
The British Embassy out there (UAE) should look favourably at that.
.. also helps that you also worked there, have met her, dated her etc etc.
Best of luck