$2500 deductible! That is awfully high! The way deductibles work though, whether or not your insurance covers your visit is irrelevant, as you have to pay the first $2500 either way, and your bill is less than that. The charges will also, I'm sorry to say, be whatever they are trying to charge the ins. company. (network discounts are given before it even goes to the insurance company, not after it goes to the patient) I'm sure if you call the hospital though, they will understand you paying in installments... at least I would hope they would be, as long as you are making an effort.
Is it a 2500 per VISIT or per YEAR deductible? If it is per year, find out what your per visit is... because that is what you are responsible for.
Wish I had better news - good luck!