I have to disagree about the antibiotics for an ear infection. If not treated, and ear infection can spread to the sinuses and brain eventually. Respiratory infections may also cause ear infections. With something this close to the brain I would not hesitate to use antibiotics. Although some ear swelling can be from tumors, most are infections. Take a look at these links, and especially the last one for what can happen when left untreated:
https://www.backyardchickens.com/t/831156/really-nasty-ear-infection-in-a-silkie-hen-graphic-pics
https://www.backyardchickens.com/t/...r-lobe-possible-mareks-tumour-or-an-infection
https://www.backyardchickens.com/t/...-large-hard-mass-growing-behind-his-ear-photo
Eggcessive is right - from those photos your girl's ear is looking worse - if it was me I would really be looking at antibiotics now, even though I don't like using them as a rule. I wouldn't be trying to push the infection around in the ear - I'd leave it and try to treat it now.
It would be best if you could get a vet to prescribe you some antibiotics, but failing that, something like amoxicillin that you have left over in your medicine cabinet will also work - you simply need to work out the dosage for chickens as opposed to humans. If you aren't sure then let us know what antibiotics you have - type and strength, and we can help you work it out.
If you decide to go the antibiotic route then remember that it is best to give the medication directly to the bird on small amounts of food or by dropper onto the beak. Don't just put it in the water and rely on the bird drinking enough to get a full dosage.
Let us know what you decide, and how things are going.