Oh Wow!!!! I also was on prednisone a couple of times, once was very high doses for about a month, the stuff makes you psycho. Good grief. It sounds like you are perfectly normal but got tangled up with mind altering drugs due to your UC. Of course I'm not a psychiatrist and have not even recently stayed in a holiday inn express so I'm not claiming to know you but if it were ME in your shoes .... you only got these last Monday??
Okay in that case drop the Lexapro right now. It doesn't even really kick in until you've been on it several weeks. What's been helping you is the benzo (Klonopin) and it does an extremely good job eliminating anxiety. If you are suffering this severe anxiety after such a traumatic series of events you might indeed need to treat it but the trick is to get the maximum benefit of the benzo without becoming physically dependent or developing a tolerance and the way to do that is to not take it daily. Keep it to the lowest dose possible (try half what the doc told you, it might work!) and take it no more than two or three days consecutively, then take a day off of it. If you need it again cycle this a few times - a very few.
These types of drugs cause reactive anxiety very quickly which means your anxiety can become worse than it was before because your brain "recalibrates" to being on the drug. So what you really need to do is allow your brain to naturally heal from the trauma and the benefit of this drug is to give you a kick start - get your brain off the hamster wheel it's stuck on. Viewed this way they can be very useful which the FAA understands and is why they limit to short term use.
But you do not want to take it daily for 59 days then stop cold turkey. You could be thrown into withdrawal as that long could get you a bit "hooked". That would be the last thing you need!
My advice is to view this drug as only one item in an arsenal to treat your anxiety. You need to bring other tools into play. If you don't exercise take up something even just long walks. Look at your diet and make sure you aren't having blood sugar swings from too many carbs or allowing yourself to go too long without eating. Get plenty of "good" fats, they satiate and relax the mind.
Also remember that acute panic attacks are self limiting. It's their very nature to make you feel like it's an emergency and you must do something now (like reach for a pill) but in reality they will pass on thier own in a few minutes. I guess recognizing this would come under "cognitive behavioral therapy" so hopefully someone is giving you that too.
The idea is to kick you off the amplifying feedback loop that is the nature of worsening anxiety. Break the cycle. Use the Klonopin only to put a stick into the spinning wheel then quickly withdraw it and use these other tools like braking the rim with your hand as it starts to slow. Klonopin can tamp down the worst of it when nothing else helps but should not be viewed as a complete and single treatment. Time and distance and your improving (hopefully) life will see it recede.
There are some herbal supplements very good for anxiety but like any psychoactive substance use these with caution, however in general they are milder and safer and much less addictive than prescription drugs and they have the benefit of being a nonissue for the FAA. If you have trouble sleeping due to anxious thoughts especially on the days you aren't taking Klonopin try Valerian root. Be very generous with doseage (increase until effective). There are many others too much to go into here. Alternative medicine is a huge subject but if you are intelligent and selective and do your homework it can be extremely helpful.
What happened to you is the combination of several traumas and I've been there, that happened to me. A single trauma like a death or illness or job loss is one thing but when you suffer multiple major hits in quick succession it's like being body slammed again and again without sufficient time to recover in between. You can't regain your equilibrium before the next one happens. While mentally healthy people can absorb one shock reasonably well, when coincidence (in my case) or cascading results (like from your UC) bring several within a short span of time, even mentally healthy people can need up to several years before they start feeling like themselves again - and even then there will always be scars.
I can't answer your certification questions, just point you to these good doctors here; listen to them and they'll get you through it. I can just tell you that it looks from here you are having a "normal" reaction to very extreme circumstances. There is a new normal in your future and it will come.