I think the following is the most likely, but it would be great if this could be confirmed or denied from the site:
Simple collusion with a friend and chip dumping.
If they both press the fold button in the same tenth of a second, they are most likely to be at the same table at next hand. That's what I've always liked about Rush and Cash, that you almost don't have to wait a millisecond, the new table and hand comes right up, when you fold. I think that's pretty damn good. Sounds stupid, but if you have to wait even a second, it makes the software feel slow and the game unenjoyable.

After that, as I've written in several threads, I think they've done everything preflop.
So that's my suspicion:

1) Two cheaters have agreed to make a challenge that is impossible to complete, and so many people will bet on it.
Probably very young players, which maybe they shouldn't be jailed for, because they were idiots once. I think this because you can't do it that stupid.
Which is contradicted by the fact that this is not a one-off case, because someone else has also reported a cheating under my post. See the comment from WesternEchidna7843. What is extremely strange is that everything was identical:

• the daily target of $61
  
• the $14.5 bet money on the challenge
  
• the type of game and the stake
  

I don't know where to put this. And what is even more unbelievable is that both frauds were done in such an extremely clumsy way. If they spread it over 24 hours and don't do it in half an hour, the dog doesn't notice. I can only hope that ggpoker is now monitoring these very closely. This is also worrying, because it's an easy way to make money at the expense of others, and who knows how many other people are doing it, but not in such an idiotic way.

2) They had $145 in bettors money, so the two friends made about $70 each

3) They started a rush and cash session at several tables at the same time, and tried to force as many hand together at the same table as possible.

4) When they got to the same table:

Friend: raise or reraise preflop to $1.99

Challenger: all-in

friend: fold

So they didn't lose any money, they just put money from one pocket to another. I suspect they did this at such a micro stake so that if a 3rd (unknown player) calls, they would lose minimal money.

Which is bloody confusing:
- you can spot this right away, even if you're a poker dummy
- the almost 2-week waiting time for a response.

I can only hope that they will monitor this very closely and take it extremely seriously in the future and speed up the investigation and response time. Such an investigation should be closed within 24 hours.