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The only concern, when you set out minimum qualifications and then don't follow them for one individual, is whether or not others that you rejected could make a claim of discrimination another basis.
The issues you'd be concerned about would be discrimination allegations based on race, gender, age (taking a younger person rather than one over 40) or disability discrimination.
If the rejected applicants can't make a rational argument to support an allegation of discrimination based on one of those factors, then there would be no other legal ramifications.