"So, I cannot truthfully do anything but leave f8615 lines A and B empty."
That is incorrect. If you are subject to § 1(g), which you clearly are since you meet the criteria of § 1(g)(2), § 1(g)(6) requires you to provide a parent's name and Taxpayer Identification Number (generally, the parent's SSN) and requires that parent to provide you with the TIN.
