Which Branch? I believe Army and Marines would likely have to greatest chance of granting a waiver. The problem with most ROTC Scholarships and Commissioning Sources is they are formed to fill "operational" slots, unless you can find a "Reserve" AROTC slot, then limited duty slots open up. Not real sure how many slots are available, the academies get first shot at most of the limited duty slots.
IF, you can afford college (FAFSA, Academic Scholarships, Work Study, in school employment at the school, etc) it would be a lot easier to get a Direct Commission slot for the aforementioned fields, as DC is not providing front line officers, but support personnel. Once he is in, who knows, maybe he gets that front line billet