The signatures are electronic and verified via the passcode, no? Yes, I would think the wrong DL could be a major issue. (My kids are past loans, but D1 didn’t have a license, either.) You need to run through scenarios with the student and the what if’s. Can you be a silent listener on the line while he calls, then cue him to the next question? Can he authorize you, in writing, if needed, to speak with them on his behalf?
Somehow, you need an accurate explanation of exactly what the roadblock is.