If it were me, I would go to the ER of the BEST hospital in the area. They have signs saying that if you are very ill or in pain, they are required to treat you regardless of whether you have health insurance or not. She can always dispute the bill later. I have a friend that simply could not pay her massive debt to the hospital for treatment of her uninsured husband's Lyme's disease. She had to write to several people, but eventually their bill was fully taken care of and he received the best treatment he could get. If your mom is really that sick, then she needs medical attention now, and I wouldn't worry about the cost. Don't let them tell you that they don't know what is wrong or that she's ok because her vitals are stable. Make them give you answers.
Hi - sorry to hear your Mom is so unwell. If her gastroenterologist "thinks" she has Crohn's, then they need to do proper testing, i.e an endoscopy of the small intestine and/or colonoscopy of the large intestine, with tissue biopsies, to make definitive diagnosis. Ulcerative Colitis (you mention possible colitis) and Crohn's, although both auto-immune disease, are in fact very different diseases and treatment needs to be tailored to the specific disease.
I live in England where thankfully we have socialised medicine and don't have to pay for consultations, treatment or hospitalisation, just a small fee for each prescription drug.
I do understand from my Endocrinologist that there are "county hospitals" in the US where patients without insurance can get medical treatment, but I don't know where they are.
Hope you can get this sorted out.
Take care,
Liz.