You will need to meet their academic standards somehow, whether that is in the way of GCSE/GCE or otherwise. I would call each and every universitys' admissions office and discuss your individual circumstances. In my experience admissions policies vary greatly between universities, some of them demand that the letter of their policy is followed to the full, others are more, well, enlightened.
In terms of turning a blind eye, it appears to me that exceptions are made but only where an applicant has academically sound higher or equivalent qualifications; to insist on them going back to take, eg, an English GCSE might be considered ridiculous.