does anyone know how to expedite a referral process?

During an appointment in January with the optometrist it was noted that my child's optical nerve is bulging, which raised concern. The optometrist mentioned that they will send a non-urgent referral to Sick Kids, but I have yet to receive a phone call regarding an appointment.

It is now April, and despite multiple attempts to contact Sick Kids, I have only reached voicemail and have not received a response to my messages. I am worried about my child's condition and was wondering if there is any way to expedite the referral process or if I can go directly to the hospital to arrange the necessary procedures?