Sorry to hear about your grandmother. It surely qualifies for an expedite request. Please file under category ' extreme emergency situation' and explain the reason on call. You may raise Ombudsman request today as it will be 90 days by the time they see it on Monday. I provided offer letter and I-797C form (OPT receipt). A doctor letter would make your request stronger. So, if you can, include that as well. Yes, that is the correct link. Don't worry, we all are with you. Good luck and hope for the best.
Just FYI, when you submit the Ombudsman request, you won't see your receipt details in the confirmation email body. Don't worry, it's a bug in their email. I didn't want others to have that confusion( whether details went through or not).