I’m glad you found that! So, yes, the obvious explanation is that they’re using weighted gpa’s. If that is the case, then this applicant would appear to be a likely admit. A conversation with an Admissions Officer at UMD could confirm this or provide an alternate explanation. I would advise the OP to make this call or talk with their high school guidance counselor to see if he/she knows how this works at UMD.
Regardless of whether this student’s chances are likely or toss up, he should apply and file early (EA) to maximize his chances for admission at what should be his cheapest option.