Well it might bring up question about your commitment to anyone, airline included, if you had just quit RAF from a bursary and failed a flying course, not least questions about your ability to undertake any intensive flying course.
If you are going for bursury, you should be commited to that one route, and any other deviaiton would surely raise questions with anyone.
Who exactly would you be gaining references from if you had failed a flying course as well? Work hard and it won't happen!