The park had on social media that the event was full and there were no open spots for additional guests at around 4 that day. I have no info beyond that.
That doesn't really mean too much. The event required registration, but registration was free.
Anyone that would consider potentially going probably signed up to the point where they ran out of the allotted capacity.
How many actually went is a different story.
For example, I signed my kids and myself up, because I really wanted to go, but after picking my kids up from school the tunnel was so backed up that we wouldn't have arrived at Water Country until about 6pm.
With the gas prices right now it's hard to justify a 3h trip for 2 hours at an overcrowded event.