"Would they loose if Paychest became successfull?"
I'd love to see any feasible argument for the idea that a market maker like Knight could be brought down (financially and criminally) by shorting a non-reporting company like PYCT.
Feasible means the nonsense about a 4 year plan to burn the shorts is excluded. ;-) Market makers make tons of money in legitimate ways day in and day out- with big board and pinks. They don't need to worry about PYCT.
The fact that there's only 2 or 3 people here in a world of about 6.9 billion people that seem to think so it rather telling. ;-)