Help with dwarf apple tree

I have a potted dwarf apple tree that we really want to save. I am currently working on stopping and treating the powdery mildew. I’m afraid it also might have fire blight. I remember some of the leaves wilted away but was still attached to the stems and I believe I read that was a symptom or sign of fire blight. I have attached some pictures if I could get help identifying any diseases, etc. and most importantly any suggestions on how to treat or what to do. Thank you in advance!

I have not had any experience with fire blight so I don't know what it looks like.  In reading about fire blight, I read that it might be Cedar Rust.  Do you live where there are cedar trees or junipers?

Here are some threads that might help:

https://permies.com/t/82875/Yikes-Fire-Blight-Returns

https://permies.com/t/47552/apple-illness-ID

https://permies.com/t/140029/permaculture-projects/Cedar-rust

Are you keeping it in the pot out of necessity, or have a spot that it could be planted in the ground?

We are renting so we haven’t been able to plant it in the ground

I would get the biggest pot you could find to move it into, which will give the roots more room to grow.

I would also remove all of the current soil, and replace it with cool compost from plants, without manure or hot compost so it won't burn the tree, if you have it, which will give the plants a lot of nutrients it will need to help naturally fight off the diseases. You could buy an organic compost soil if needed.

If you have a way to catch and collect rainwater to water the tree with, that would be best, as tap water is probably treated with chemicals that will generally kill most soil life. It can be best to not overwater, as wet feet can stress the apple tree and make it more succeptible to diseases.

Do you know what variety the apple tree is? Certain ones can be more susceptible to diseases than others. Also depending on your location certain disease pressures can be higher.

I hope this helps a little!