It is certainly possible. You might be wise to consult with a DUI attorney. It also might be a good idea to have your dad write a declaration explaining exactly what happened. It also might help if your dad is on the vehicle's registration and insurance. Good luck.
Yes, this is technicaly a violation. Consult with a local attorney who specializes in DUI; many offer free consultations. Bring your father to the consultation. Let him know he may have to testify at a hearing.
(I saw your other post regarding this and asked a question- this clears that up)
Please know that despite all of this, you still may be violated.
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