Rumdada-
In my opinion, you should tell whichever doctor you see first that you would like some clarification regarding your condition, your test results and your treatment plan.
The problem is that when you're really miserable with the beginning symptoms of UC, you are not in the best condition to hear and understand what the medical people are telling you.
It's a good idea to bring someone with you (a second set of ears) and before going, make a list of questions you have and take notes when you get answers.
You can get some ideas for questions from the responses you've had.
It does sound strange for you to have multiple colonoscopies in a very short time frame. If you feel you're challenging the Dr's authority, you could ask about
that in the context of "I want to check if my insurance will cover more than one."
I never agreed to take prednisone because of the potential adverse side effects. Did your GI or anyone inform you of the risks?
Pred reduces symptoms but does not cure UC. I believe most doctors use it (short term) to get a flare under control but prescribe less dangerous meds like Asacol and mesalamine enemas for long term "maintenance".
Hope this information is helpful. I wish you the best of luck.
Let us know how you're doing