Sorry to hear you're having a hard time Sean. Now take a deep breath and lets get this in perspective.
1) MRI/Catscan vs IVs and Orals - Compromise with them. Yes you will do IVs, BUT they WILL schedule you in for a scan of your lungs. Lets face it, a tune up is not going to do you any harm, annoying yes, but can only be a good thing, it's not like you are on them all the time, thereby running your body down. Don't give in. You haven't had a scan for over ten years, there is reason enough. Throw the word 'negligence' around and be pushy until you get what you want.
2) you are worried about your dream job happening and then you perhaps being stuck to an iv pole at the time - i wouldn't worry, if they want you badly enough, you can disguise what is going on long enough to seal the deal. If you are planning on being up front with them about your health, then go to every interview, appointment, assessment they ask you to do, without fail, even if it nearly kills you. THEN tell them you were on IVs the entire time and that's about as bad as it gets for you, at this stage anyway. That should impress them no end.
3) If you are feeling well in yourself, not off colour, good appetite, good exercise tolerance etc, there is nothing seriously wrong for you to worry about. You have had hemoptysis in the past and have then managed to get rid of it for years. Something nees tweaking again is all and if anybody can work out what that is, it's you. You will get this sorted in no time.
Stop worrying. You don't need to. <img src="i/expressions/rose.gif" border="0">