This is very confusing for your mother and you.

Spots on the brain can come from many things.

If they used the fluroquinolone antibiotics on the ear infection
like Cipro or Levaquin? These cause confusional states in the elderly. High doses especially provoke older patients.

There are other drug combos that will do this too. If you'd like I can try and evaluate that for you. But since she is getting better, you may not need that.

With cancer, I have seen patients where the "primary lesion" is gone, and only the metastasis remains. That is because the body has some ability to get rid of cancer cells. This ability is less in the brain.

But as Koala says, TIAs, strokes, MS, even some parasites like from pork, can appear as spots in the brain. So time will tell what is going on with your mom.

Severe depression can appear to be like dementia. When the depression is treated, the dementia-like features often go away.

I hope things continue to improve for her.