It would make sense for them to take away your responses. They may want to preserve secrecy of their prompts either because they want to reuse the prompt or they don't want to give the general "feel" of the prompt for future applicants to practice from (You can compare it to AAMC releasing another FL that is very similar to the actual exam, it leaves more openings for applicants to practice, but on a smaller scale). In addition, I'm also assuming they used PROFIT for MMI, which might mean the question is "intellectual" material belonging to the company. Maybe the took away the good responses because they don't want you to be using it to coach future applicants or sell it to BeMo or whatever.
Now, as usual, I think it is a computer error or some spaghetti code issue. 1) One possibility is that it is completely random, the computer program just glitched the heck out and randomly chose. 2) It is a binary indicator. Accepted = absence of your text, vice versa for rejection. 3) Maybe your response reached above/below a certain score, but does not tell you whether or not you will be accepted. 4) Someone commented on your writing, which made the programming glitch. 5) You passed or failed some screen along the way, but not 100% an acceptance.
I think depending on when the text disppeared/appeared can give a hint regarding what it means. If it literally happened today, which is pretty close to the admissions release, then it could be more indicative of a final decision. If people's disappearance/appearance happened individually or in waves, it could just mean your app was reviewed and/or reached above a certain score.
Tbh I'm happy people are embracing trying to find out what these things mean. Compared to the beginning of the cycle people would be like STOP INVESTIGATING, YOU'RE JUST NEUROTIC AF, LET IT BE, ADMISSIONS PROCESS TAKE THE WHEEL. Tbh imo we should totally test these theories. If the process insists on being as vague and non-transparent as possible, it'd only be natural for humans to try to find out whatever information they can from it. Imagine a world where someone wants to systematically investigate a phenomenon, but their peers be like YO STOP YOU'RE BEING NEUROTIC, JUST. TRUST. THE. PROCESS.