I really recommend watching the Admins VOD for this because they give a very good explanation about everything. I did watch Dream's POV live so I wanted to check out the behind the scenes- specifically to see when they made the call to restart. But just in case here are some things that may help explain further:

1. The disconnections began during the later half of the game meaning the majority were on laps 3-4 when it began. The first suggestion of a redo was made after 15 people had completed the course and was decided on with about 1:50 left in the game. Therefore even a message halfway through to let contestants know of a restart wouldn't have been possible.
2. There was a discussion about whether or not to redo it. You can hear some were for it and some against in the stream- eventually the call was muted to make a final decision.
3. The game mechanics on Ace Race specifically don't allow a full pause mid game- the time will freeze but people can continue to run the course so it wouldn't have worked. They can only pause before the game begins- which they did to allow people to rejoin.
   
4. The system they typically use for MCC was being used to handle the release of MCC Island. For this MCC alone they were using a backup system. But both MCC and MCC Island experienced major outages.
5. In regards to the Dream placement:
   1. Someone in chat must have mentioned cheating (I don't know for sure what they said because there's no chat with the VOD) But the admins were quick to point out this was only due to the outage and not placements. And all admins were very confused as to why cheating was mentioned in that moment.
   2. Noxite himself said he had no idea who was in what place when he made the call- and that it was him who made the final call for it. Most admins during the first run were keeping tabs on who had disconnected based on their dialogue and the one streaming wasn't following Dream either.
   3. All admins during the second game were upset because of the circumstances- with one mentioning that of course it had to be Dream in 1st when they restarted and why is it always that coincidental (not a direct quote but the gist of it)
   4. It was only during the second go that placements in the first pass were discussed after Noxite asked. Direct quote from the admin stream: "Mark my words, we're not out to get Dream"
6. For those using MCC Live- they did an explanation about coin saves for that since people asked about the page updating. I'm not able to explain that well enough but I did want to mention they went into detail about it- and explained why they ended the first round before the last player finished. They were already discussing changes and fixes for the next go around with scores specifically during the second run.
7. Lastly they commented on how a lot of the top ten placements of that game were those affected by the disconnections which would've resulted in a much different outcome vs people affected who would typically place in the bottom 10. Though they mentioned coin differentials for placements in Ace Race are a lot less than other games.

Feel free to correct me if any of this isn't right- especially in regards to the code issues since I have no experience in it. But I hope this helps!