Why is my cat's raw ear not healing despite e-collar and ointment?

Hi, I am sorry to hear about Sparrow's ear. The inside of his ear looks clean as you have shown in the picture. The back/base of his ear unfortunately looks quite infected. It is great that you are keeping the Ecollar on to prevent him from scratching the ear. Sometimes topical treatment alone will not be able to heal this type of infection.
The area looks very moist, either from infection or the ointment(s) that are being applied. Typically when cats have an infected area on their skin, we want the area dry and do not put on topical treatments. This wound would most likely heal very quickly with a visit to Sparrow's veterinarian. The doctor can clip and clean the wound with medical grade gentle cleansing solution and get Sparrow on antibiotics. The antibiotics (which needs a doctor prescription) is the main treatment to get this to heal.
I cannot recommend any further over the counter treatments that would allow this to heal. I am sorry about that. I would recommend to keep him indoors only, keep the ecollar on, and hold off on the ointment so the area can dry up. The veterinary appointment can hopefully happen soon and Sparrow will be on his way to healing quickly.
Best of luck.