Broken leg and maybe a tumor?!?

[Debby]

We have a female squirrel I’m thinking about 10-13 weeks (still on milk because she’s under weight 240grams) and she came to us with a broken leg we were told we couldn’t split it because it’s so close to the body so we have her in a small fish tank till she heals up. She’s doing great! Running bouncing moving and she doesn’t even act like it hurts anymore (she broke it about 2 weeks ago maybe a little less) now she has a large lump maybe a tumor? And I would like to know if any one else has handled this and is there anything that can be done?
In the past we fostered a dog with the same kind of leg brake. He had surgery to fix it and developed the same Tumor we were told it was scar tissue and nothing could be done other then another surgery which wasn’t necessary because the tumor wouldn’t effect the quality of life. Is this the same kind of situation?