Think about normal shame, it acts to dissuade bad behaviour. Here, the bad behaviour is declaring intent to enter (and to produce something) before failing to do so. To help motivate you, you are promised to be shamed if you fail to submit something.
Obviously you should try to avoid this, but getting shamed once is hardly the end of the world. You'll get thrown into the SHAME pit, but there is potential to get out!
Here is the pit: https://chooseyourstory.com/forums/writing-workshop/message/28494
To get out, just enter another contest later and actually submit something.
Now, if you get shamed while in the SHAME pit, you'll go down deeper, and if you get shamed THREE times, you'll be banned from future site contests.
TL;DR
Don't worry about the consequences, you should totally enter because it is a cool contest and a great way to get your name out into the community! Worst possible outcome is extra motivation to enter more contests!
