After following the great tutorials from http://www.raywenderlich.com/ on how to submit your app to the app store from square one I started planning my beta test program.
<We have also faced with this problem couple of times and possible reasons might be;
Due to the screen shots, did you upload your files to exact location "http://www.becomingapps.com/en/ota/"
location? When you give this URL during enterprise export.
Second possible reason we have seen is mismatched App Id's
.
The only difference I can see is in the CodeSigning, ensure both lines under Adhoc point to your certificate.
Second thing to verify: You did not mention the plist that is created during the "Save for Enterprice". Did you upload that to your server, too? And does your link point to this plist? Check out this answer for the plist stuff: How to send the build to already provisioned remote person's iPhone
In case you haven't solved your problem, I think you can't use a wild card in your ad hoc profile. It should have the full ...com.becomingapps.dilemma signature.
You also have to upload both the icons, but I'm assuming you did that since your screenshot shows a custom icon.
It's worth the effort to get this working, my customers love it.
I've had this exact problem even where, like you (as far as I can tell), everything is done right.
What I discovered is that if you've EVER had the url to the plist file or the app file incorrect then your iPhone will always fail to install. There's some kind of cacheing going on where the phone fails to download the updated plist file if it's previously downloaded an incorrect one.
The fix I've used is to try a different phone (that hasn't cached a previous version), or to make a new version at a different URL. Sounds crazy, but it worked for me!