Hey, TechM, the first thing I noticed is that your poster is only 1300 pixels wide. Considering that it contains a lot of non-vector content (eg, all of the logos, quite a few lines of text that unfortunately have already been rasterized text, etc.), the poster is going to have lots of fuzzy areas if it's printed to the 18x24" size you specified. In addition, I would comment that 18x24" is *tiny* for a display at an expo. People will have to approach it to within 3 or 4 feet to be able read everything, to have the qr code be readable by a cell phone, etc.
I would suggest printing it to at least 3 x 4 feet, and possibly larger. Since parts of the poster will look fuzzy at 18x24, you can imagine how *really* fuzzy they will be at a larger size.
Also, one of the main fonts you used, MODERNART, is not part of Adobe's Typekit, and a quick search didn't turn up anything. Can you tell us where you got it? Are you married to its use?
Can you supply the various logos in either vector form or as a bitmap, but at a much higher resolution?
My take on the situation is that at the very minimum, 2 or 3 hours of work needs to be done, more if you can't supply some of the bits and pieces in a suitable form/resolution. Personally, I would start from scratch, including a complete redesign.
FYI, this is not something I would be interested in doing. However, you might want to consider putting a notice in our fee-for-hire section. Read the guidelines (sticky to the top of that section), write something up, and I'm sure you will get more interest.
Best regards,
Tom M