Urgent Gouldian Finch with Lump

[Chickie01]

I'm sorry if I posted this in the wrong area, I am new here and really need help. I've successfully kept 2 pairs of gouldian finches in a flight cage for 3 years with no problems. Until about a month ago I found a lump on 1 females face near beak. I separated males and females now. I am not a breeder, these are my pets. Some others have said possible scaly face mites, but I have treated with ivermectin pour on 2 times with no improvement. All other birds look pristine. They do not have access to outdoors. Now she is balding and FAST! Could this be a tumor/cancer? I also just brushed her skin and beak and put a sample under my microscope, and I do NOT see mites. Photos are of the first day I found this issue and then updated photo from yesterday. Any help much appreciated.
Taken yesterday


Last week


When first discovered 2 weeks ago.


...

 

[Pixiebeak]

It can be a Papillomas. A wart thst birds can get in beaks and feet typically, not uncommon in finches.
But I can't be sure , as the first pic seems to have a injury by it , that improving some in other pictures, so it could be an infection.